By Josh Wayner

Josh Wayner’s taken it upon himself to challenge what everyone “knows” as far as barrel length, velocity and accuracy are concerned. According to his results, the conventional wisdom ain’t all that wise when it comes to longer-barreled ballistics. The only question then is, if you buy in and go with a short barrel, can you stand the noise?

Abstract: This is an independent scientific study that has been conducted in western Michigan. This study addresses the misunderstanding of the concepts related to barrel length, muzzle velocity, and accuracy in a rifle . . .

Elements of the Study: This study was conducted with a set of standards that do not necessarily correspond to all manner of firearms. The combination of weapon and ammunition used for this study was carefully determined and analyzed for the best results. This study was conducted with what the author and fellow researchers determined to be the most precise materials and methods available gathered from expert input and other existing studies.

The platform used for this is a Shilen match barrel which began at 26 inches in length and ended at 13.5 inches. The chamber is of standard SAAMI specification in 308 Winchester and the barrel features a 1:10 right hand twist. The ammunition used for this test is of several types, all of which are of corresponding lot numbers. At each range, handloads were used to seek out advantages given the barrel length by modifying the bullet and powder. This data is included gratis and represents the abilities of the weapon system when tuned ammunition is available.

For this test, the barrel was attached to a Savage short action target receiver in a Scally Hill Systems MK4 Mod7 folding chassis. This test measured all three variables at the same time in the most similar conditions available. Testing was conducted at Southkent Sportsman’s Club in Dorr, Michigan and Chick-Owa Sportsman’s Club in Zeeland, Michigan. Firing was conducted at a distance minimum of 100 yards and a maximum of 540 yards. Informal ‘field’ shooting was conducted on private land at safe targets out to a distance of 900 yards, accurately measured by satellite using Google Earth.

Ambient conditions were on average 70-75 degrees Fahrenheit with 40-50% humidity at an elevation average of 670 feet.  Shooting was conducted with a 16x SWFA SS optic, a piece well noted for its durability and ruggedness. Velocities were obtained using a chronograph and extrapolation of shooting results. Group size was measured with a micrometer. Five shot groups were used to measure accuracy. Firing was conducted on standard IPSC silhouette targets at all ranges.

This study does not aim to look at terminal effects, rates of drop and drift, combat effectiveness, ethical viewpoints, or legal/political issues.


This section is included here as a semi-abstract to address commonly held beliefs regarding barrel length, muzzle velocity, and accuracy. These results are backed by the data collected below.

Explaining Barrel Length:

Belief: a long barrel is required for accuracy when shooting at long distance.

Fact: In no part of our testing was barrel length a determining factor in accuracy. At a distance of 100-540 yards, there was no discernible difference in accuracy between various barrel lengths. This performance translated over to unknown distance shooting with all barrel lengths at ranges out to 900 yards. At no point in the testing was a short barrel a hindrance once marksmanship fundamentals were observed and proper flight data was applied.

Explaining Velocity:

Belief: Now that we know that accuracy is pretty much the same, short barreled rifles lose too much velocity be effective at long ranges.

Fact: This is a double-edged sword. The 13.5-inch length could propel a 168 grain Hornady TAP round at an average velocity of 2390 fps, which is hardly slow. That is only a decrease of around 315 fps from the 26 inch length (25.2 fps/in), and vindicates many researchers who pioneered velocity discussions. There was no noticeable critical difference in accuracy at any range. There is a downside to longer ranges and reduced velocities, that being increased susceptibility to wind as range increases. Increased drift is not the end of the world, though, and if measured properly, can be overcome with ease.

What is more is the differences in velocity across loads and barrel lengths. The issue with barrel length and velocity was also interesting in that, across all bullet weights, the extreme variation is only 31% (110 VMAX @3202 and 208 AMAX @2215). In the most accurate load, the 168gr HPBT handload, the velocity difference between longest and shortest was only slightly more than 15%. The round with the least variation between barrel lengths was the 175gr Federal Gold Medal Match with slightly less than 8% variation.

Explaining Accuracy in a practical sense:

Belief: “The time I put five shots into a cloverleaf is the time I did everything right.”

Fact: This is the greatest misunderstanding in the world of accuracy and shooting. In our testing, no matter the ammunition used, the weapon showed that there was a natural fluctuation in regard to group size and point of impact. This has been determined by other studies as well, even those using ‘rail guns’ and heavy benchrest rifles. Accuracy, at least in our testing, was determined to be more akin to a ‘cone’ than a grid in that the accuracy of the rifle had an average maximum radial spread of .765 MOA over all barrel lengths.

In layman’s terms, this means that the barrel could fire an indefinite number of rounds into a circle with an average diameter of 1.53 MOA, which is not all that impressive. However, it must be understood that accuracy does not work like traditional manuals dictate. As an example, a man takes his new rifle to the range. He sets up his targets and fires several five shot groups. His groups are respectable by most standards, with most clustering at around .75 MOA. He sets his zero and continues to fire.

Here is the important part: he fires another group and gets a ‘flier’ one MOA low and left. He discards it and continues, discarding all the fliers he gets. Now it gets hard for him to figure out. He shoots five shots and notices that he gets a .25 MOA group, but .8 MOA low and .45 MOA right. This is a great group, and he scratches his head and adjusts his scope to it. He shoots again, but prints a wide group measuring 1.2 MOA across, but now shifted off his zero. He assumes that he has run his luck out, packs up, and goes home.

What has happened here has happened to many people. What our friend did not realize was that his gun was never zeroed at all. The tight cluster he got was not the time he did it right, it was a statistical possibility that comes from firing. In reality, the man had a rifle that was not shooting .75 MOA, but rather he was printing groups and ignoring his most important ally, his fliers. These are critical to rifle accuracy and are not mistakes.

Statistically speaking, the rifle he has may actually fire a maximum group size of 2 MOA at 100 yards, which sounds terrible, but really isn’t. The vast majority of his rounds will probably impact at a radius of around .5 MOA of his true zero, or even less if he has a good combination. What he did not understand was that there is nothing wrong with a rifle that may throw a round out even 1 MOA or more, it’s all within the statistical level of accuracy that the rifle is capable of.

The results of this study were very telling. Overall, as demonstrated in the accuracy charts, the shortest barrel length provided the most consistent accuracy across the board and the longest length proved to be the least accurate with the same loads. The data also shows that the so called “MOA” a rifle can shoot changes with distance. The groups at 100 yards show very good, often benchrest grade accuracy, and then at extended ranges, they show a natural increase in group size. Across the board, all the loads tested across all barrel lengths showed this. Across all loads and lengths, the average at 900yds was .765 radial MOA or 1.53MOA. Compare this to the 100yd average of .206 radial MOA or 0.413MOA. That’s right: the average across all lengths and loads yields sub half-MOA at 100yds and just over 1.5MOA at 900yds.



This test obliterated what was previously thought to be fact. Not only was it determined that short barreled rifles are easily as accurate a those with long barrels, but we also discovered what we see as a key to viewing accuracy in a practical sense. In an age of misinformation, hard fact can be hard to come by. The internet is full of armchair know-it-alls and trolls a plenty, but for the most part, these can be ignored. Mental preconceptions of the researched concepts are still deeply entrenched in a more or less Napoleonic era of the theory of arms. Most of what is commonly argued about small arms is false and based on opinion. A quick look online reveals hundreds of arguments on topics like 9mm vs. 40 S&W vs. 45ACP or AR-15 vs. AK-47, none of which are based on fact or on the need of the individual in their realistic circumstances.

If anything is to be learned from bullet selection, it is that match quality bullets have a distinct edge in accuracy over military and hunting bullets. The match bullets tested produced significantly greater accuracy than their military or hunting-type counterparts.

This study is not aimed at the promotion of using any particular barrel length, brand of bullet or load. The reader must look at their own situation and determine what the most valuable features are in a rifle.














Josh Wayner is a senior at Grand Valley State University studying Applied Research Science in the Interdisciplinary Studies Major. He has been a competitive shooter for nearly ten years and has eleven CMP medals from Camp Perry. Josh is also the owner of Scally Hill Systems and is constantly developing and testing new things. Long range shooting has been his passion for many years and he continues to push the envelope in modern rifle design. 

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159 Responses to The Truth About Barrel Length, Muzzle Velocity and Accuracy

  1. Very impressive work. I would propose a hypothesis that barrel harmonics from a longer barrel introduce an instability to the overall flight path that has an increased effect on point of impact once projectile speed drops over extended range. (Basically the barrel is “whipping” the round a bit.) Shorter barrel lengths do not have this issue due to much better stiffness.

    Proposed experiment… Setup a high speed optical micrometer to track center line of the barrel tip during the firing process in X and Y axes normal to the bore.

    • This has been validated by a few suppressor manufacturers. Hanging a can on the end of a gun seems to quell barrel harmonics and actually increase accuracy.

      • They might also reduce the impact of muzzle blast turbulence on the projectile. Without tracking the barrel, it’s hard to differentiate the two effects.

        • If the bullet is well above trans-sonic speeds, how can flow turbulence in its wake possibly affect the bullet?

      • Don’t exclude recoil in this factor. Suppressors do reduce recoil and as such affect accuracy. Possibly not so much from a physics prespective, but definately from a shooters. The reduction of recoil will definately increase you accuracy. I have a braked gun that has a supprssor that screws onto the break. Accuracy is not apparently shifted by the addition of the suppressor, point of impact does on long shots. But we can’t rule out geometry here either… lots of factors in this equation.

        True some difference is noted but again harmonics is dampened by the addition of the weight. I woud be interesting to get a computer plot of the harmonics effect along both the X, Y axis at the bore and the linear dimension of the barrel to note axial deflection.

    • I haven’t been shooting rifles (much) for long, but I’ve noticed with my .308 Rem. VTR that when you touch your muffs to the buttstock after firing you can hear the barrel humming like a tuning fork for 15 or 20 seconds. It might be more pronounced since it has a non floating barrel and a synthetic stock, but I’m sure all rifles do this. My theory is that when the bullet jumps through the leade it slams into the rifling and sends shock waves down the barrel ahead of the bullet. In order for the waves to resonate the barrel must flex. This doesn’t necessarily adversely effect accuracy – if the bullets leave the barrel at the same velocity they should all be timed with the resonance the same. They may shift slightly to the left or right or up or down, but they should all shift the same way. But switching loads could move the point of impact in unpredictable ways like left or right. I would think that as barrels get longer they need to get thicker to control the flex.

      It would be interesting to read (hint TTAG) a comprehensive article about the physics of a rifle shot.

      • Dude, you need to ditch that crappy soft Remington stock and get something free floated. Vibrating for 30 seconds like a tuning fork is not normal.

      • “In an age of misinformation, hard fact can be hard to come by. The internet is full of armchair know-it-alls and trolls a plenty, but for the most part, these can be ignored.”

        Haha, no kidding. Just look at these comments!

    • Yup, what Pwrserge said. Barrel harmonics. You can tune the load to the barrel but you may have to compromise some velocity or you can tune the barrel harmonics to the load. Hence the reason you see so many target guns with barrel tuners on them. I find it interesting his study didn’t mention a barrel tuner or harmonics when the gun he is using in the picture has a barrel tuner on it over a flash suppressor. Theres an excellent page on barrel harmonics here along with animated gifs.

    • Spot on comment here, I concur. The same tendency was observed between the 1917 and 1919 Browning Machine Guns. The 1917 has a barrel support (to off set the barrel deflection from the water jacket) and a mass of water around the barrel, the 1919 does not. The difference in accuracy for the same length barrel is way different, the 1917 performing very nicely. Cyclic rate was tuned down (lightening the bolt) as a means to control the 1919; not only in consumption of ammunition but accuracy. The 1917 needed no such adjustment.

      • In reality the 1919 barrel is supported at the end of the jacket just like the 1917, the barrel diameter is 1.25″ which is double that of the 1917 barrel and even without the water it damps fine. Cyclic rate of the two measure nearly the same even though the 1919 has a booster to help increase the recoil impulse. My guess is that the much heavier barrel needs a boost to help with reliable operation. The internals of the 1917 and 1919 are identical and interchangable. When set up on the same type of tripod they tend to shoot very similar groups. The 1919 tripod is generally the lightweight M2 unit which is quite wobbly where that of the 1917 is usually the 1917A1 tripod which is very solid.
        Just a thought as this has been my experience in working with the brownings for the last 20 years or so….


    • “drewtam says:
      October 1, 2013 at 19:01
      If the bullet is well above trans-sonic speeds, how can flow turbulence in its wake possibly affect the bullet?”

      The propellant gases are travelling 4-5 times faster than the bullet itself. Once the bullet leaves the muzzle the gases overtake the bullet and give it a kick in the ass, which is one of the factors involved in bullet yaw and instability in the first portion of its flight.

    • Interesting study but completely agree with with the harmonics element. To me, if the loads were not tuned to the barrel length, then the only usable data is in the subsequent velocity. The “accuracy ” data means very little to nothing…am I wrong?

  2. Great piece of work, conducted with scientific precision and accuracy. Would have appreciated some footnotes to track down some of the other research quoted.

    I wonder how the Grand Valley State admin is going to respond to this work.

    • I don’t know how Interdisciplinary Studies handles it, but the engineering program didn’t much care WHAT the project involved….

      While I was taking an industrial controls class one group of students built an automated trap thrower which was, at the time, the only trap thrower on the market with a TRULY random pattern of throw.

      Another group of students built a project with several metallic silhouettes with a boatload of sensors attached. The idea being they could capture impact velocity, impact energy, etc.

      Lets face it, generally speaking firearms research is cool. It’s bright, flashy, and impressive when presented during University functions. And I know GVSU LOVES flashy student presentations.

  3. As a researcher you should be aware that these graphs are not meaningful without error bars. For example, what is the maximum error in the powder charge for these cartridges? What are the dimensional tolerances of the bullets? To what degree is the barrel crown flat?

    My intent is not to disparage your work, but point out that drawing conclusions from this type of study is a bit disingenuous because there are far too many issues impacting accuracy and even muzzle velocity to provide a reasonably accurate description of estimated error. Without that your data cannot be interpreted properly. For example, if your estimated accuracy error is as little as 0.3 MOA, almost all of your accuracy data points must be interpreted as being identical.

    These are the reasons why there is “conventional wisdom”; there are too many factors involved just within the cartridge itself, let alone the rifle, to provide a good-faith estimate of error, and as a result accurate interpretation of the data becomes impossible.

    • This is correct.

      Another “experiment” ignoring the majority of the variables involved and not taking error into account. This data says very little, but when coupled with technical sounding language and graphs the average guy thinks he is looking at good scientific evidence.

      This sort of thing happens rather frequently on this site, unfortunately (and everywhere else on the internet…).

      • I do want to point out that there IS a point to be made here, which is that a longer barrel does not inherently mean greater accuracy. This can be stated without an error estimation. It is also something that some manufacturers have begun to realize, as some sniper systems have been developed using relatively shorter barrels more comparable to carbines.

        • Can we really conclude that? The comment above about the experiment lacking any error or standard deviation information is a good one. If the error bars are large, then it is entirely possible that longer barrels are still more accurate. It could also mean that shorter barrels are more accurate. Without understanding the error, we can’t tell which is true. It’s like the author pointed out with regard to shooters who get one tight group, adjust their zero, then think their rifle is sighted in. We can’t look at the data and tell if we were in the middle of the statistically possible range, or way out on the fringe. We haven’t been given enough info to judge.

        • “Longer barrels are more accurate” only applies when using iron sights where the longer barrel allows a longer sight radius which lets the shooter sight the rifle more accurately. Scopes provide the same sighting ability regardless of barrel length.

        • My second comment is “longer barrel does not INHERENTLY mean greater accuracy”. That is not saying that that they are definitely NOT more accurate, just that there is no evidence to suggest that there is something specific to the length of the barrel that equates 1:1 to better accuracy. There is a difference.

        • Why don’t we have a conversation about efficiency? IMHO, what you want is a barrel that is long enough to impart as much of the energy in the powder into the projectile as possible, and a projectile that will dump as much of that energy as possible into the target.

      • Not entirely true. The data is simply incomplete. However, it does give reason to question the classic longer barrel / more accurate gun myth.

        • What it suggests to me is that a longer barrel length will result in greater velocity, up to a point, but that the longer barrel is more susceptible to change through heat distortion when fired for more than three shots, thereby resulting in worse accuracy. Interesting to note as well that in most charts, the optimal length for overall repeatable accuracy at range was 18″.

        • It is standard practice to show the error and/or standard devation of the data shown in a study. That is how you do good science with proper statistics. Kinda the short of it.

        • There’s more truth to “longer barrel – more energy” than “longer barrel – more accuracy”. But optimum barrel length varies based upon load.

        • I would think this sort of information could be added per a request from the reader. Well, instead of bewitching the guy and calling his research meaningless and all …
          Point being,
          Replicate it, or refute it.
          Without that, what are you doing, but being argumentative? I agree, more precision to the study could be done, but he made good effort. Someone should extend it with their own research then.

          Nice work to the guy that cut down the barrel and went through the trouble to do the research.

          Now, like I said,

          Those that insinuate the evidence is not there.
          Go on, refute it.
          or replicate it, give the guy some props, and extend it in his honor, LOL

          Thanks to the guy that put in the work.

    • Kyle,
      this experiment was not designed to count every single powder kernel the cartridge case. off the shelf components and cartridges were used. the tolerances of M80 ball are obviously not the same as federal gold medal match. the reason that error was not factored in was that we were not testing over 100 barrels and 100,000 rounds of ammunition. we counted the flyers. Every single one. the displayed velocities and accuracy numbers are averages, which is clearly written. plus, as a student of the gun, you should understand that the bullet is the truth and there is no such thing as error, just more data.

      • Josh,

        It is standard scientific practice to report your percentage of error with your data sets. This comes down to proper reporting and getting as much out of the study as possible. Excel can do it for you in a simple spread sheet.


    • Thanks Kyle. You are spot on. I have shot, at a quick estimate, over 2 million rounds in my lifetime. It has been my experience that I have been more satisfied with the accuracy of a Barrel OVER medium length for the platform. I have found practical experience in real world conditions to be more accurate a determiner than scientific studies which are all flawed and need to have an error factor figured in. Reloading a good number of rounds myself, I can say that matching bullet acceleration inside the barrel to desired velocity and then exiting the barrel immediately seems to give best results in my experience. I will accept all the other points about harmonics and bullet diameter variations, but all these issues will need to be prioritized. In my estimation, behind proper match of barrel length and bullet acceleration. I don’t think I need to go into how this effects the other things like harmonics and such. Kyle, glad to know there are some actual good brains left!

  4. As a scientific point, it’s a firearm. Weapons are used (past tense) on people, firearms are used on paper.

      • Using a sword to cut a melon means its a cutting instrument. If you want to immediately evoke the visceral response of the uninformed or hoplophobes, keep calling every firearm a weapon. Winning the narrative means controlling the language. If we cede control of the language (assault weapon, weapon, high-capacity, etc), we will lose.

        • Yes, words have connotative meaning, and that meaning can scare some people. Personally I have no problem calling firearms weapons; it is their purpose and design to cause the destruction of whatever they are aimed at. Just as a sword is not forged with cutting brush and food in mind, even though it can be used this way. All weapons are tools, not all tools are weapons. To me, trying to convince anyone that we truly believe not all firearms are weapons makes us look stupid, and is beside the point. The point is that we all have the right to keep and bear these weapons, not to make other people feel better about that fact.
          On a side note, I do agree that it would be more objective and properly scientific to refer to it as a firearm, as that is a more specific descriptor.

      • Semantics is the scientific study of meaning. So yeah, it’s scientific. In the interest of using exact terminology, firearm is more accurate.

  5. I’ve never held the belief that a longer barrel makes the GUN more accurate. A longer barrel does give you a flatter trajectory due to higher velocities, which tends to make the SHOOTER more accurate.

  6. Of course the order of barrel length testing was from 26″ – 13″… so… I’m sure the shooter didn’t get better with the platform over all the rounds down range. And I’m sure the breaking in of the 13″ of rifling that was never cut down had nothing to do with the conclusions. And I’m sure the crowing for each barrel cut down was confirmed to have the exact some profile… And I’m sure there are about a dozen other variables that weren’t accounted for in this testing.

    Not discrediting this in the least – it’s good data and certainly supports the notion that a shorter barrel is more accurate… but a publishable paper on the subject it is not.

    • With a hand-lapped match barrel like the Shilen used in the test, ‘breaking in’ is just wasting the accuracy potential of the rifle. Breaking in barrels and barrel settling is something done for factory barrels with rough bores. Polished barrels start out the most accurate they will ever be, and degrade in accuracy for every shot after that (very slowly) due to wear and loss of that polish. Or at least that is what top barrel makers say.

      And counter point to him ‘getting better with the system’, fatigue has a bigger impact on the shooter than practice with the gun, if the shooter is already competent.

  7. Very excellent work. This is off topic, but isn’t MOA technically a measure of precision and not accuracy? Yes, I know accuracy is the word that is commonly used in these types of tests and everyone knows what is being measured…

    • You are correct. Accuracy refers to whether a given shot is on target. Precision is whether a collection of shots is consistent.

      • I prefer repeatability over precision. Precision also implies the degree of error in your ability to take measurements.

  8. Good reading. I’d also love to see more work up in regards to barrel harmonics. I’m also curious on the barrel crown question.
    Machine rest?

  9. THIS is what I would like to see in our future. Careful research with all the data presented so that it is open to reasoned peer review, analysis, and application.

    Not that it’ll change the mind of “experts” like Jim Carmichael et al. His experience over time requires us to listen, but not be overawed and think he really is omniscient.

    Thank you, thank you, thank you for your work and setting the bar.

  10. Good to see an article that takes a closer look at “what everyone knows”.

    From a purely non-rigorous, personal anecdote standpoint, I have found that a short, heavy profile barrel (18″, DPMS LR308B) tends to maintain accuracy over long shooting sessions, even when the barrel heats up quite a bit. It would be interesting to test this against longer barrels of different thicknesses, with and without flutes, firing enough rounds to reach a specific barrel temperature at the muzzle. As soon as I receive my $5 million grant from the gummint, I shall begin the buying frenzy (oops, cross that out) and testing.

  11. I’d like to see a comparison of downrange velocity for each barrel length and at what distance they hit the transonic region.

    The upward trend in group size with distance makes me wonder about wind while the data were being collected.

  12. I am a competitive shooter as well for 10+ years. I have been a faithful reader, until its demise, of Precision Shooter Magazine and they had done a lot of work on the subject. Things I find lacking in this study. Cutting a barrel down inches changes it to a new barrel essentially. The crown rifling is now different. Also changing the load/bullet every time you change the barrel changes another variable that would actually prove their thereom wrong. They should have maintained the same load across all barrel lengths to maintain consistency. The Velocity of 2300 from 2600 is huge for a distance shooter. Especially when the distance shooters are trying to be 3000 fps for maintaining supersonic velocities into the target. The drift factor and wind was not a concern for the test but it is a huge concern when you are trying to hit your target. A longer barrel does give an accuracy advantage when maintaining a long distance load accross all barrel lengths because of velocity or the ability to increase pressure on the bullet before exiting the barrel. If barrel length did not matter then a 2.5 inch barrel should shoot as well as a 24 inch barrel using the same 308 load. There is a sweet spot barrel length for loads, you don’t need a 35 inch barrel for a 6 mm round but you need more than 18 inches to shoot 1000 yards with a 6.5×284.

      • I didn’t get that impression from the statement… “handloads were used to seek out advantages given the barrel length by modifying the bullet and powder. This data is included gratis and represents the abilities of the weapon system when tuned ammunition is available.”

        Powder charges and bullets should have been loaded and optimized for the long barrel and then maintained as such to see if there was an atributable change in accuracy as you chopped the barrel. This is to maintain a constant as you examine the variable. You put too many variables in motion and you will get spurious outcomes. You would be surprised what a lot change in the same powder or primer change does to my scores at competition. Benchrest is a lot about scientific methods where you establish a load by only changing one variable at a time.

    • You don’t want the handloads to be the same: the whole point of handloading is to tune the load to the barrel’s natural harmonics, which should change with barrel length.

      I want to know how the handloads were developed? Optimum Charge Weight (OCW) method? Audette ladder test? Quickload? SWAG?

  13. Entertaining reading. Many valid responses. Stimulating Conversation.

    In the end, I will simply, select a rifle that physically fits within the constraints of my operating parameters, next I will “test” my rifle of choice with various “available” ammunition until the most “proficient” combination is discovered, then I will tune my rifle to its optimum “precision” using aforementioned “proficient” ammunition, and finally, I will practice with it until I become “accurate” with the resulting combination.

    As long as I am confident that I can reliably eliminate the intended target, at the specific distances that the rifle will be utilized, the rifle is effective. Everything else is just for show and tell. 😀

  14. Thought I had zeroed my 7mm08 bolt action w 18″ barrel until i read this. i don’t think my rifle is grouping well at 100 yards but barrel began clean and now has 20 rounds through it. Tried two different types of bullets in 120 and 140 grains, from different manufacturers but not sure what to think now. I had fliers at 100 yards with both boxes, which opened my groups up to 4″. Not using match grade ammo and feel the trigger is a little heavy but does this seem too big? Rifle is a ruger american compact, the fore end is not perfectly square to the barrel and ruger says they will not take back for servicing unless it is affecting accuracy. What say you?

  15. Coooooooooooooooooooooooool. This jives with my (non-shooter, haha) intuition about physics and guns.

    Now we just need good replication. :p

  16. Some thoughts:

    1. It has been known among some gun makers for years that shorter, stiffer barrels are more consistently accurate. Some of the more accurate .308/7.62 bolt guns I know of have 18 or 20″ barrels.

    2. Barrel length affects velocity more when you tune the load for the barrel length. As you lengthen your barrel, you can change your load to use slower powders. Using a slow powder with a short barrel simply results in a huge muzzle bloom. Using too fast of a powder in a long barrel can result in barrel failures. Using a slow powder in a long barrel, now you can start to see some results.

    Generally speaking, if you use the right load modeling s/w, you can develop loads with easily (or formerly easily) available powders to produce complete combustion of the powder charge about an inch (or a bit more) behind the muzzle. This is about where you want it, regardless of how long the rifle barrel is.

    3. Match bullets, as you found, really are better. Especially the all-copper bullets. They’re more concentric, better balanced, more uniform in weight and their lower Bc’s mean that they’re affected by wind less than bullets with lower Bc’s.

    4. Where barrel length does affect your accuracy is when the sight radius depends on the barrel length. Using an optical sight (a scope) eliminates this variable. If you had aperture sights (or even buckhorn sights) on the barrel/receiver, you’d start to see the errors add up as your barrel length (and therefore your sight radius) decreased. One of the things that led to the accuracy of Sharps rifles in the 19th century wasn’t that the barrels were much better than (eg) Winchester lever guns, or the bullets, loads or powder was better in the Sharps than in a (eg) Winchester. It was that the Sharps had a much longer sight radius and better sights.

    5. You didn’t mention how the barrel was re-crowned every time some length was taken off. I’d be interested in knowing the uniformity of the crowning process.

    6. Groups were measured with a micrometer? That seems a bit excessive – and difficult. I think the groups were probably measured with a set of calipers.

  17. Sorry, but this is like confirming that the sky is blue.

    Short barrels are more accurate than longer barrels, in the abstract. This is because there is less harmonic distortion in the barrel.

    Longer barrels, especially with iron sights, are easier to shoot. Not only is the sight picture extended, it has a higher velocity, which cuts down on time to target, and less time for the wind to affect the bullets flight path, less lead needed for moving targets, and distance judging is not as important.

    At long ranges, minor differences in velocity produce huge differences in drop.

    Sure, I could strap down a 13″ barrel, find out exactly where the bullet will land, move my target there, and the rounds will produce a nice grouping, a better grouping than a 26″ barrel, but in the real World, where I don’t know the exact distance, that extra velocity is a huge factor in hitting what you are aiming for.

  18. Hummm, I’m old fashioned I guess, as well as old. I take my ’06 and zero it to hit 2″ high at 100 yards via my Leupold scope. I then go deer hunting and shoot at deer any where from 40 yards to 200 yards. All my deer are one shot kills. Scientific enough for me.

  19. So for the 208 amax handload, having an 8 or more inches shorter barrel will increase accuracy 10 fold? Is something else going on in the handload or rig that might favor the shorter barrels? If so you’re not isolating the variable, if not and simply a shorter barrel means 10 times more accuracy there – then it’s a bit of a laughable claim, no? I mean, how do you come out with that data and believe you’re showing causation?

    • Unless I read it wrong and they aren’t direct comparo’s and it’s showing the difference over yardage.

  20. i would say that the reason a short barrel may seem stiffer is rather simple, the bullet and the gas expanding in the barrel would offer up quite a bit of energy, as there bullet is proceeding down the barrel the gas behind it is changing in pressure, since the barrel acts as a chamber for the gas until the bullet ether gets to a port or the end of the barrel. i think that pressure would be much higher in the chamber at first then as the bullet travels the length of the barrel the pressure would drop as the space the gas is compressed in expands. i think one reason that shorter barrels can be more accurate is cause the gas pressure is more uniform thought firing, reducing the whip effect of the barrel. maybe the shorter barrel does not have to deal with as many variables in pressure and vibrations. this is of course assuming the same barrel diameter and composition.

  21. “Increased drift is not the end of the world, though, and if measured properly, can be overcome with ease.”

    Don’t be fooled by this, a 10mph wind at 900 yards at a muzzle velocity of 2390 = 2.8 mils (4000 DA at 90*)

    2.8 mils of drift = 24.3ft of drift

    Hmmm…good luck.

  22. Just an opinion but the “longer barrel in more accurate” really applies more to iron sights than optics. A longer sight radius can be more precise than a short one but putting on a scope removes sight radius from the practical accuracy equation.

  23. It’s very easy for a passel of wannabe experts (ex = has been, spurt = drip under pressure) to sit on their brains and criticize based on their own opinions of self worth and what they THINK is their expertise. Didn’t see ANY of them state that they had or were even willing to try to ACTUALLY perform similar studies by actually firing the rounds and keeping notes that truly reflect the resultant findings. Josh did a wonderful job of presenting food for thought for us common, ordinary grade flunkies who use our rifle for hunting and recreational shooting. It’s a guess but I would bet that most of them can’t really shoot well enough to hit a washtub from a benchrest at 100 yds; but they will never admit that. Good job, Josh. WAY TO GO.

    • See my earlier comments. Precision Shooter Magazine has done work on the issue. Asking for a guy’s log book is like asking for the Colonel’s secret recipe. The best shooters don’t share the details, just know from experience.

  24. Article was a nice Term paper.

    The information found within helps tell and verify the true story commoanly know among long range shooters, that for every inch of barrel you loose roughly 25 fps.

    Other than that it is still misleading and unfactul to try and say a shoter barrel is as accurate.

    Speed is king in long range shooting and velocity is the key.

  25. Well….I have a semi-auto .22 rifle with a barrel length of 22 inches and a single shot bolt .22 rifle with a barrel length of 21 inches. The single shot bolt .22 will put multiple rounds through a single bullet hole @ 10 yards, but the best the semi auto will do is make the hole a tad bigger. For 100 yards, the bolt gun has a lot bigger bullet drop. I’ll have to measure it sometime. You wouldn’t think one inch shorter barrel would make that much difference. For what it’s worth, I’m using Winchester long Rifle bullets in both guns, out of the same box.

  26. Sure would be nice to cut my 26″ 300 win mag barrel down to 16″ or 18″ to make it easier to run around in the woods with. I’ve always wondered if I really needed 26″ of barrel to have a reliable hunting rifle. Articles like these always tempt me to just go for it and see what happens…if I were only a rich man…

  27. You said, “What has happened here has happened to many people. What our friend did not realize was that his gun was never zeroed at all.”
    This makes me believe I don’t know how to zero my rifle. Wanna elaborate on how to do that correctly?

    • Using your scope and using a rifle rest aim for a specific point (mark one) and shoot say… 10/20 rounds. Go to your target and mark the center of the grouping. With your scope exactly on your original mark secure your rifle so that it cannot move during adjusting of the scope. Look into the scope before adjustment and ensure you are on your original mark – without moving the rifle, adjust your scope to the new mark you just made (the mark indicating the center of the grouping). You are now sighted in.

  28. I am liking this test performed by Josh Wayner – I am not liking Josh’s condescending attitude that speaks to us like “I am a competitive shooter so I am right, you are wrong, here are my results from this test, be enlightened by me.” Had he stuck to publishing the results only (instead of explaining things to us in “layman’s” terms) it would have made for a much better read. Regardless…

    I applaud his efforts and the test is certainly worth something. However he used four different barrels. One of each length. If even one of his barrels had a defect (such as the 26″ barrel) then his results would be greatly skewed. For this reason, I do not put much weight on the test. Like a grouping of 10 or 20 shots, had he used 10 or 20 barrels of 26″ long vs 10 or 20 barrels of 16″ long and compared those results it would carry greater weight. If I take a rifle and shoot one shot and hit a bulls eye does that mean that rifle is accurate? The ammunition is accurate? There are so many variables. More variables should have been eliminated. Likewise with the rifle itself. If you are going to perform a test on barrel length it would be feasible to test several barrels of the same length to ensure a more accurate test.

    The comparison itself must be accurate – not just a grouping obtained from a select few barrels.

  29. Not implying anything about this test specifically, but I often wonder about the design of experiments when it come to guns. Something that I have always been curious about is how did the “five shot” sample size became the standard. Who picked it. I have always found that a 20 shot group would tell me much much more about a rifle than a five shot group. Others have said that a five shot group is easier but that is not much of an answer for a physics / engineering problem. I knew a guy who bought a 300 Master Blaster, he shot four five shot groups, cut out the best one and kept it in his wallet.

  30. “Increased drift is not the end of the world, though, and if measured properly, can be overcome with ease”

    With ease huh? The author is basing his velocity doesn’t matter on this statement, with the assertion that wind can easily be overcome. That is simply not true, wind is a bitch and anyone that says otherwise is lying to themselves.

  31. “Informal ‘field’ shooting was conducted on private land at safe targets out to a distance of 900 yards, accurately measured by satellite using Google Earth.”

    Measured by satellite? How does that work? I didn’t know Google earth offered a featured that allowed one to task a distance measuring satellite. Or, do you actually mean you measured the distance off a satellite image using Google Earth? That imagery is plus or mins 2-3 yards at best, not real accurate.

  32. I don’t think you have to look any further than F class and 100o yd bench rest winners to see what is the accuracy king.

  33. Yes very interesting. I am not a rifle guy since my M-1, M-14, M-16 days, long ago. No complaints for all, they accomplished the necessary. As a pistol guy I prefer at least a 4 inch pipe. I have a snub nose I can not hit a barn with over 15 feet but I have seen people do much better. Training and practice makes the difference. For self defense it is about 12 feet or less, fast, first, final or fatal.

  34. The author is getting pretty harsh treatment by some but he should be commended for his work in procuring and sharing these data which are certainly valuable and informative. The only criticism I would offer is the over-interpretation of some of the data and use of the term accuracy rather than precision.

    The effect of distance on radial MOA would be more interesting if there were a way to absolutely control for wind, but even a 1-2 mph intermittent stirring will result in a distance-dependant dispersion equal or greater than reported. Also, as noted by someone else, real-world cold bore accuracy (not precision, i.e. grouping) will be reduced by reduced velocity.

  35. There are trade offs on barrel length , optimum powder charges for bore size and the length required for top velocity .. The .308 Winchester while a accurate round doesn’t have the case volume for a optimum powder charge for its bore size ,it takes around 70 grains of slow burning powder to reach optimum and 44 inches of barrel to reach maximum velocity using figures that come from Krupp research in long range artillery guns..
    Not that this isn’t a good test of a standard military / hunting round ,yet it wasn’t a optimized round or a optimized barrel length .. Iv’e seen guys buying 22 inch barreled 30-06’s, Remington has got on the short barrel for accuracy band wagon.. My reply to these guys is why didn’t you get one chambered for .308 ? You most likely cut your velocities to .308 levels any way esp with factory ammo that’s intended for 24 and 26 inch barrels.. My message to the average hunter / shooter is don’t run out and cut your 24 or 26 barrels to 18 thinking you’l get a great edge in accuracy you lose the velocity needed to combat wind drift and lose accuracy for practical use .. If it’s a magnum rifle and you cut the barrel even a few inches you no longer have a magnum that extra barrel length most magnums is there for a reason .. To take advantage of the extra powder in the case.. Thanks

  36. Humm…. Perhaps we should clarify the actual definition of accuracy. Are tight groupings with minimum MOA references produced ANYWHERE on a target accuracy? Couldn’t we perform a similar experiment using any caliber of firearm at 100 yards to produce tight MOA references. Then we could make the argument that no particular CALIBER is more accurate than another due to similar MOA groupings as well. As long as you say things like: “Once marksmanship fundamentals were observed and proper flight data was applied”, or “This study does not aim to look at terminal effects, rates of drop and drift”. How can we even consider the term “accuracy” without these references?

    As a dumb redneck myself, I tend to define accuracy as hitting what I am aiming at. In the practical world this means I don’t have a spotter, range finder or wind drift calculator to correct for every shot at varying distances. I aim and shoot. I hit what I aim at, both near and long distance with little correction. This is due to the CALIBER and the VELOCITY that I have chosen. The latter of which is some 600 fps faster at 26″ than it would be with a 16″ barrel length according to your data. If I put my rifle in a vise and cut the barrel to 16″ I am absolutely positive that the increased rigidity of the shorter barrel would produce tighter MOA values. In doing this, I would have to apply “proper flight data correction, bullet drop compensation AND wind drift correction to compensate for the inferior trajectory due to DECREASED velocity approaching 30% ( interpolation of your data) in order to hit “where I am aiming”. Interestingly, this would be true DESPITE the tighter MOA grouping from the more rigid barrel.

    This is what I would call “NOT ACCURATE”. But hey,…it’s a great MOA grouping! Where is it on the target though? On the first shot? Before the correction factors have been applied? I’ll bet my longer barrel on the first shot placement for my definition of accuracy any day.

    Accuracy and MOA groupings are two different things. I agree with the data, as long as the right perspective is considered.

  37. This was a very interesting study. Thank you.

    As for the velocity issue, since the limitation to how much energy you can put in a bullet is the chamber pressure and subsequently barrel pressure, the longer the barrel the more PV energy you can impart to the bullet. A completely tuned propellant system at each barrel length would show V^2 roughly proportional to the length.

    But as noted, the greater length makes more whipping from harmonics and the longer barrel requires substantially more tuning, perhaps more metal. Think about what happens to a hose when you turn the water on.

  38. Glorious article and study. However, it still remains a fact that shorter barrels on precision long-guns look silly. True, there is no effect to accuracy, perhaps an improvement, but aesthetically – a long-range rig with a 20″ (or shorter) barrel looks impotent, imbalanced, abridged, snubby, and weak. There is no denying this – agree? Yes? No? Bueller? I grant exception to a short barrel with a suppressor attached, or that Scally Hill in the photo with what appears to be a large diameter shroud – the terminating fixtures balance the look. 🙂

  39. I am not surprised by this, but I would point out that many whom were in the military are. Military weapons also have to fire tracers and this is why they have the 1/7 twist and not the ideal 1/12 twist that is optimal for the 5.56 round. When the military went from the M-16 A2 variant with the 20 inch barrel and moved to the A4 which in most versions has a 16 inch barrel there was a significant drop in accuracy. I am sure there is not as significant a drop on a civilian version of the AR-15 with the 1/12 twist even with a shorter barrel.

    I would also point out that the powders of most bullet manufacturers are engineered to be fired out of shorter barrels these days with the explosion in popularity of the AR’s with the 16 inch barrel. If you are shooting at distances over 500 yards you will see an accuracy difference between shorter and longer barrels, 450 yards is simply too close a distance to magnify those results when the 16 inch barrel is shooting bullets engineered for 16 inch barrels. Move the distance to 700 yards and get a load optimized for the 20 inch barrel and then compare the 16 (using the 20 inch optimized round) and the 20 inch barrel and you will see a significant difference.

    If the point of the study was to say there are 16 inch barrels competent to 450 yards I could have told you that before the study but it is nice to see it on paper. Ruger 10/22’s are accurate enough and can drop modest sized game at those distances no problem. Someone was expecting that a .308 (in any size barrel) could not accurately reach out that far? The end of the story is this: at 450 yards is just not that far for modern rifles of shorter barrels with the current selection of ammunition. I would like to see this study revisited at 700 yards with a comparison of the 20 inch barrel and the 16 inch barrel with ammunition optimal for longer barrels (read slower burning). I enjoyed your work Dan!

    James Estrada

  40. I think the article and study over generalizes bbl length vs accuracy. If what it says is true then why do most LR, F, FTR guns have 24 to 30″ bbls? Having said that, the gun that holds the IBS HG 1000yd 10 shot record wears a 20″ bbl I believe.

    • @JimmyJames Also consider that if you are shooting a round where say a 1 in 12 twist is optimal a 16 inch barrel with a 1 in 12 will be at least as accurate as a 20 inch barrel with a 1 in 7 twist. If the ammunition they are shooting is optimized for a 16 inch barrel, there will be very little difference in the accuracy. If the ammunition is optimized for a 20 inch barrel you will see a significant difference in accuracy the further away you get.


  41. Stability is not a function of barrel length. Heavier bullets are longer bullets, so a faster twist is needed for stability. But a faster twist does not create an accuracy problem for lighter, shorter bullets.

  42. I agree with you Desertrat but I would put it slightly different.Every barrel/bullet/powder has a combination that works ideally for it. A good example would be that if you have a 20 inch barrel, you want a powder burn to the end of the barrel and no more, you would not want it stopping at 16 inches (which would be optimal for a 16 inch barrel). But that powder might be fine in a 20 inch barrel if you use a lighter bullet. Desertrat is right in pointing out that stability comes from the spin on the bullet and bigger bullets need less spin and thus fewer twists. The reason compromise twists (twists that are good at shooting a multitude of ammunition) are now common is because people just go buy bullets and don’t designate barrel length. The guns are made more for utility than optimal use (squeezing every foot out of the round you can). Most people I know that are “in the know” (know more than I do ) tell me that most bullets can get about 20% more out of them if the bullet/primer/powder combination is loaded with a specific gun in mind (i.e. a 5.56 with a 22 inch barrel and a 1 in 12 twist) would work best with say (for example) a 50 grain bullet, powder X and primer Y.

  43. I’m much more of a hunter than a target shooter. Been reloading for the ’06 since 1950. Once I get a load inside of one MOA, I’m pretty much satisfied.

    Funny how sorta-universal a 1:10 twist can be. My ’06, .243, AR .223 and a Ruger bolt .223 are all 1:10 and all shoot sub-MOA. Barrel lengths of 26″, 19″, 20″ and 22″, respectively.

    I certainly would not argue about “ideal” combinations of powder and barrel length, but in that context I figure I must be running 95% of absolute optimum in my loadings and barrel lengths. 🙂

    I have much respect for guys like the Houston Warehouse crowd, or the Gale McMillans, but they are far more serious students of ultimate grouping than I.

    • @Desertrat you are right that there are many great 1 in 10 rifles in the sub 300 range of caliber. I am not necessarily looking for target ability from premium loading but that is the discipline if you are a target shooter. I prefer the idea of getting as much out of a round as possible because I work in law enforcement and my first call ever was a shooting where an officer (from a Desert city in Arizona coincidentally) called for assistance on a shots fired call. The suspect terminally wounded through the heart by a 9mm at a range of about 60 feet ran for a block and a half with a loaded gun after being shot. I also heard from the shooting team on the site that a fatally wounded suspect fighting on for 1 to 2 minutes in not uncommon if they are on drugs like meth. I started taking interest in rounds with more power but less chance of over penetration, which is when my study of reloading started seriously taking place.

      • Not having been in a shootout, I sometimes wonder if people shoot as a non-fighter fights: One punch, stop and look for the effect. One shot, and stop and see what happened?

        I’ve sorta programmed myself such that if I have to shoot in self-defense, I’ll shoot until the hostility stops.

        My handgun preference is the 1911. I’ve used both .45ACP and 9mm versions. One thing I tend to like about the 9mm is that I could stack an entire magazine in a pretty small group when going at max speed.

        Your comment about the meth-induced resilience reminds me of the Moros of Mindanao and their “juramentado” condition against the US military, back those long years ago.

  44. The post strikes me as a defensive bit about how velocity doesn’t matter, short barreled .308 is better for military applications than short-barreled 5.56, and why no one needs a more powerful cartridge than a .308, or a longer barrel than 20″, both of which strike me as aburd. But I should be specific:

    my area of study has been mostly in making weapons more compact and useable for real-world scenarios.

    They’ve been very thoroughly studied by the US and NATO militaries. This isn’t new ground. Neither considers velocity “an abstraction.”

    It appears that a large number of individuals are fixated on the concept of velocity and that bullets must be moving at Mach 11 and call the remaining rounds in the magazine ‘Goose’ and ‘Iceman’ to be taken seriously when in flight…… You always want to get more of her, but you don’t really know why other than just superficial attraction. The allure of a high velocity number on your ballistic card is just too attractive for most to resist.

    This bit, above, is silly. Those shooting light bullets at distant small game know they need high velocity to stand a chance given wind. Those shooting very heavy high-momentum bullets at thick skinned dangerous game know that momentum and sectional density are much more important than velocity for their purpose. It simply is bad manners (and laughable) for you to assume that other more experienced hunters, snipers, and equipment designers do not know what they are doing, but that you do.

    In my personal opinion, the .308 Winchester is by far the best candidate for chambering in your short barrel.

    Which is why the vast majority of them in both military and civilian hands are chambered in 5.56. And shame on the Russkies and Chicoms for not chopping back those AKM barrels!

    No other commonly available cartridge gives you the ability to push a 168gr .30cal bullet out of about 11 inches of rifling at 2380fps while not wasting powder or barrel life. In other words, .308 is the weakest .30 caliber rifle cartridge, except not quite as weak as the .30-30. Got it.

    In point of fact, I don’t think that any rifle of any caliber really ever needs a barrel over 20”. I’m not alone in that sentiment, as many Magpul fans or long range students out there who own The Art of the Precision Rifle will know, cowboy patriot Todd Hodnett states that he will never own another .338 Lapua over 20” again.

    No rifle of any caliber …needs a barrel over 20″? Do you live in a cave? Have you ever gone hunting with any caliber larger than .30? Are the militaries of the world simply building all their sniper rifles wrong because they didn’t consult you?

    The thing with shorter barrels is that you have to be mindful of what components you use to load them. And handload you must to get the best performance.

    It may surprise you to learn that this mindfulness is required when reloading other calibers as well. And remember, your custom load numbers are just averages. You’ll never know if you got a particular cartridge loaded exactly right.

    but it’s the truth: velocity is abstract. I’ll give you a few minutes to think about what kind of things you’re going to write me in the comments section. When you get back, I’ll tell you why it doesn’t matter.

    The truth is that every shot is different and entirely dependent on a host of external and internal variables.

    We never knew. Are you sure of this?

    Is running fast an abstract concept? Neither is velocity. Both are a statement of a concrete reality, the distance covered per unit time.

    It wasn’t your fault; velocity is just a vain lady. She gets worse, but the thing that you have to remember is that velocity is nothing more than an estimate that begets another estimate.

    What’s with all the “velocity is a lady…a bitch….a fair haired vixen? It’s just velocity, how fast the bullet is travelling. There isn’t any sex involved.

    Velocity is not an estimate. Perhaps what you meant was that your handload is never perfect, and you will never know exactly the temperature down range?

    Yeah, you just made a $7 noise. But don’t worry, it wasn’t your fault. Velocity happens.

    This argument says “since your velocity will vary slightly, you should only use cheaper cartridges.” Then you’ll miss by even more, but it will cost even less. Stick with White Box? The more you miscalculate your ballistic data and make your sight adjustments incorrectly, the cheaper the ammo you should shoot? I agree with that. Everybody agrees with that. Don’t shoot expensive ammo until you are ready to be precise.

    The effects of temperature are constant, and velocity is constantly affected by the environment. Do you see now how velocity isn’t something that can be used as a marker of effectiveness or efficiency? It’s constantly changing; therefore, the terminal and external ballistics of the bullet in flight are changing, too.

    The benefits of higher velocity and a heavier bullet will actually be an increasing benefit when the weather is colder, the air denser: The effect of crosswind will increasingly favor the heavier or faster-travelling bullet (check your advanced ballistics calculator on a few comparisons). Increasing altitude will reduce the benefit.

    When you fire your long 26” barreled rifle at 2805fps average, that bullet has slowed down to 2380 by the time it hits 200 yards. If you were to fire your 16” barreled rifle at an average 2610fps, you will be hitting 2380fps at only 100 yards.

    Yes, the additional velocity delivers a more effective (more energetic, higher-momentum) hit, whether to a moose or a man, downrange. Unless you consider energy and momentum to also be mere abstractions….

    At a range of 540 yards, the 26” barrel yields 3.5 mils of drop from the same 100 yard zero on a 70 degree day. That’s 30% less drop.

    Drop, as any long range hunter, sniper, or paper-target shooter will tell you, is not the problem. Wind is the problem. Shooting from a rest (your pack, sticks) in the field at an elk 400 yards away…you can very quickly dial in your drop, especially with a CDS dial, but you’ll just be guessing the wind drift. You won’t be missing due to elevation. You’ll be missing on the lateral, which is why velocity and bullet mass matter. Which matters more, velocity or bullet weight/momentum, depends on conditions and the nature of the target.

    I thought you did. You can see that temperature alone can play havoc and make your 26” drop like your 16”, which is now dropping like your 13.5”. Abstract indeed. Temperature plays a huge role in how bullets fly, as does elevation and wind. So let’s close the distance a bit to a range most people can shoot at regularly without much environmental interference, like 300 yards.

    Hunters have been taking temperature and elevation into account for well over 100 years. The concepts aren’t abstract. They are calculated based on concrete measures. Abstraction is either a sets concept (mathematics), or means “impractical or vague.” Velocity calculations taking temperature and altitude into account are neither.

    So what? That still looks unimpressive? That’s like a million clicks of difference, Right? On a 70 degree day, there is only a 6.4” (2.1 MOA) difference in point of impact between the 13.5” and 26” barrels. On a 10 degree day, the difference is only 10.8” (3.6 MOA). That equates to very little real-world difference. If you happen to run a 16”, the differences are even less noticeable, those being 4.3” (1.4 MOA) at 70 degrees and 7.5” (2.5 MOA) at 10 degrees. None of this is really that big of a deal for real-world applications.

    What real world application is it that you keep coming back to in your mind, but do not describe in the article? It seems to me you’re thinking of running through the bush with your rifle chambered for a distance round, in a military situation rather than hunting. In the bush you won’t have any long shots, and with a rifle much heavier than a 5.56, you won’t be running so fast or far, either. If you are walking when you hunt, as surprisingly many of us do, you’ll lose nothing by carrying a barrel long enough to burn more powder in the barrel, rather that outside of it.

    What? How is that not a big deal? Let me tell you: all bullets drop, that’s a fact of life. Modern high quality optics can account for it as simply as clicking the elevation turret or looking through the Horus reticule.

    Drop isn’t the problem for practical shooters, whether hunters or soldiers. Wind and a stable shooting position are the problems, together with target movement, time pressure.

    “But Josh! What about wind?”….. Time, patience, and missed shots are part of the learning curve no matter what barrel length or velocity you shoot with when it comes to wind.

    Time and patience offer little help with wind calculations. Velocity and bullet weight ofter plenty of help. Contrary to the thesis of this post. Spin drift? It’s a triviality at the distances mentioned.

    That is another reason I encourage proficiency at medium distances, as there’s significantly less wind influence at closer ranges. This might be a given, but it’s a good given in that there is very little significant difference in drift between a 300gr .338 Lapua at 2800fps (.4 mil drift) and a 168gr .308 at 2380fps (.8 mil drift) at 300 yards in a 10mph 90 degree left to right wind. Even though it is twice as much, it’s only a difference of 4.4” (1.4 MOA). The thing is the .308 gets there at less than 1/5 the cost, less than half the powder, and with a weapon shorter than the Lapua’s barrel when folded. If we’re talking semi-auto, the cost of the system alone can dictate choice, not to mention the availability of parts and weight penalties. That extra 1.4 MOA just got a bit pricy, in other words.

    With a 20 mph wind at 450 yards there is plenty of difference between the rounds compared. Indeed, that’s why a .308 user in the field will want a 180 grain bullet, or a faster cartridge.

    4.4 inches is trivial? Just how wide do you think a Taliban dude’s head is from centerline? A deer’s heart? As for cost, a .338 Lapua bolt-action gun doesn’t cost five times the same quality .308. There is no advantage to a 13″ rifle compared to a 16″-barreled rifle in most actual hunting or soldiering. Running actual behind-the-lines recce in jungle would make it worth the forgone velocity, but approximately no one partakes in that activity.

    the average distance for a police sniper to fire at (not necessarily hit. Looking at you, NYPD…) his target was only 51 yards based on a 2005 report summing up over 200 sniper shots. That’s hardly far at all, but well within the realistic expectations of urban combat. At 50 yards, there is literally no disadvantage to having a short barrel. In the military, a shorter barrel isn’t something that’s new. The SCAR 17 with a 13” barrel is in use with the SEALs currently, and is no doubt the primary target of Lapua’s new 170gr offering. A shorter barreled weapon is also far easier to conceal and jump with, bonus if it has a folding stock as well.

    Police snipers aren’t distance shooters. For that matter, they are not snipers. They just use that term because it sounds cool. They’re just the guys in the department who are supposed to be able to hit something accurately with a (typically bolt-action) rifle. Nonetheless, they do buy those very expensive scopes. The last time I looked, the longest police sharpshooter kill was at 78 yards. How was this section relevant to the thesis?

    Almost no one in any military is jumping in anymore.

    2014-01-07 11.48.01

    I seriously doubt that most people who own a .338 Lapua east of the Mississippi has had a chance to fire it past 900 yards enough to become truly proficient..

    You yourself said you encouraged proficiency at medium range. Is there any reason .338 Lapua people shouldn’t also gain their proficiency at such ranges?

    I’m not going to get into the reasons why people buy the guns they do, but I will say that in America, if it can’t be done by a .308Win, it really shouldn’t be done at all. …… If you feel comfortable carrying a hot loaded .357 or .44 mag up north, realize that a 168gr .308Win, even a 13.5” one, has more force at 1/3 mile than a hot 240gr .44 does point blank. And to think, Fred Bear would have been horrified to learn that the polar bear he shot with an arrow back in 1966 could have laughed off a .308 according to some of the experts I received mail from recently. In short, a short barrel isn’t a handicap for hunting. It’s just the contrary.

    2014-01-07 11.36.09

    My hunting rifle is one of my Scally Hill Systems Mk4Mod7 systems that uses a 13.5” barrel. When folded, it’s just 26.6” long and can maneuver through brush like it’s not even there. Even with the stock in position, it’s only 35.75” overall with a 13” length of pull. It’s smaller than most AR15s out there, uses AICS mags, and it’s still a .5 MOA gun after 4000+ rounds and counting out to 540 yards, and yes, that’s an average of .5 MOA. For hunting anything in America, that’s hard to beat when size and accuracy are concerned. Not to mention, it’s the ideal sized rifle for a guerrilla sniper or armed civilian marksman in a time of unrest.

    For most realistic uses, a short barreled rifle isn’t a handicap. Considering that most hunting and shooting is done at around 100-300 yards given terrain, available practice areas, and shot ethics, there isn’t really a disadvantage to speak of. ….. Bigger bullets do not make up for poor marksmanship, nor does more velocity…… don’t get your hopes up about shooting bad guys. Go buy Modern Warfare 3 and learn to quickscope with the MSR. Trust me, it’s cheaper and you’ll only get bruised verbally by 12 year olds. Get something that you can fire comfortably, effectively, economically, and lethally at the maximum distance that you can fire at regularly. My bet is that you won’t need a 26” .338 Lapua or even a 20” .308 to do that. In other words, don’t try to make up for your shortcomings with more power. That will only magnify them.

    Can you go longer? Sure, you can. But the real question is why you would want to, knowing that you will probably never wring the full potential out of a short barrel to begin with at your typical range or hunting excursion.

    For elk, moose, and sheep hunting, you will certainly want higher velocity and (for moose) heavier bullets. For deer hunting in grizzly and brown bear country you will definitely want to carry a heavier caliber rifle with more velocity. In some hunts (the Delta Bison hunt in Alaska, for example, you’ll have to bring a .30-06 200 grain load. The .308 200 grain load is too low-energy by the Alaska Fish and Game’s opinion. Fred Bear, you will recall, was backed up by a hunter with a heavy caliber rifle.

    But why constantly compare a semi-auto SBR in .308 to a .338 Lapua? They are completely different items meant for different purposes, having different virtues. Has somebody with a .338 Lapua been teasing you?

    The smaller the better in a woman? Huh?

    • @Ropingdown I agree with much of what you said but there are generalities that apply. Yes 5.56/,223 has become more competent in flight out of shorter barrels to greater distances (just like all other calibers). Computer generated simulations and formulations have gone a long way toward accomplishing getting the maximum out of bullets and their respective weapons, While this means a 5.56 of today firing out of a shorter barrel might perform as well as or better than a full length barrel of the past shooting ammunition from a bygone era (say 15+ years) the same factors in development that made the new ammunition competent out of a shorter barrel, have also worked to improve the competency of the ammunition coming out of a longer barrel. So while 400-500 yard distances for the right short barrel (with the right twist) this was nothing remarkable in the past. My Marine Corps beat to death M-16A2 (20 inch barrel) would routinely put 10 out of 10 in the black at 500 meters (yes meters not yards) from a prone position and it was the easiest part of the rifle range qualification.

      While you are correct pointing out the average person seldom shoots at 500+ yards let alone further and thus never builds up a proficiency, let alone maintains it (as Jack Reacher pointed out shooting is a perishable skill), but does that mean you should never practice for the mechanics of such a shot? When I went to the police academy the instructors pounded into our heads that the vast overwhelming majority of gunfights took place in 21 feet or less. The first time I was going to have to shoot someone if he did not stop what he was doing I was about 20 years away, and was scared to death because mentally I had not prepared for the shot. Look if it is a range where a 5.56 (with either a 16 or 20 inch barrel)will kill you, a 7.62 or .300 winchester mag will also kill you. Just because you seldom shoot to 500+ yards does not mean you should not be able to.

      Right now we should be celebrating the enhanced competency of shorter barrels and not arguing the semantics of the newfound competency of short barrels.

  45. After going numb trying to find filtering through the most valid comments made (after trying to thoroughly understand the article), the main idea is simple…. The barrel length factor is only a myth! UNTIL you have trial & erred each individual item ie: bullet (specific weight, model, etc..), powder type and weight (and finding the sweet-spot for each in relation to barrel length), case and primer (to get really picky), the the barrel itself!!! Composition (Steel, Chro-Moly, Stainless, etc…), its crown!!! The twist was covered (1-10″),but there should be more elaborate tests with different twists per different barrel lengths. I have read lots of comments concerning fluting, barrel weight, & harmonics, and I feel these are very valid concerns which should be observed in conjunction with all of the many other factors! And, to touch on something which I didn’t read about: number of grooves and types of rifling!! I have read and believe that less grooves equals less resistance, therefore increasing velocity. How were the riflings cut? How were they lapped? There are just way TOO MANY FACTORS to get precise data…. Especially if you’re not immortal and/or financially unlimited. I’ll stick to building a gun beginning with barrel and action (whichever comes first), and then choosing a bullet, then powder type and weight, until I feel I have found the best fit with each, one thing at a time… This doesn’t include days I forget to eat or take my meds, and I shake more than I did another day.. so much stuff to consider!

  46. the arguememnt for barrel length versus accuracey is legendary and is argued at almost every level of shooting. The only shooting discipline that can accuratey argue the point is the benchrest circuit, specifically the “rail gun” crowd. Accuracy is as much a component of barre length as it is projectile weight / coefficient and powder charge. Combine these factors with actual yardage ( i’m an old guy- i like the imperial system) and the data set can be overwhelming. It is a well documented fact that barrel length will effect velocity and that velocity can be directly and proportionally tied to accuracy at given distances. If TTAG reader were hoping for a forehead slapping, epiphany like article they are probably too new to the shooting sports to intelligably argue the points.

  47. Why make this so complicated? Take the same round, same load, same twist, same everything. Anchor the different length barrels rigidly (no shooter). Put some target of sufficient size out there some distance far enough so that all the rounds don’t go into the same hole. Fire a bunch through each barrel and measure the spread of the pattern. The other stuff may be interesting but contains so many contaminating factors as to be worthless. If you must screw around with the mechanics, vary the load so that the velocity is the same for each barrel length. It is fun to have these arguments that go on for years and provide income for the different sides of the argument but like so many things, this is not a thing about opinion, it is, or can be made, empirical.

    • You were square on with your comments until you said “screw with the load until the velocities are the same”….Velocity is a vector quantity that refers to the rate at which an object changes its position.- if you match velocities out of two different length barrels, given the matching ballistic coefficients – your results will be the same “down range”. Quick basic litmus test would be to change only one variable- barrel length. And then measure the impact spread at known distances.This is science fair 101.

    • Hey, sorry I don’t check this article often! My tested load was wildly hot but very, very accurate out to very great distance.

      Win brass

      CCI BR2 Primer

      48gr Benchmark

      If you don’t handload alot, don’t blow your gun up trying to do this.

  48. As I result of reading this article I bought a 700 in heavy barrel 16.5″. It gets so much hate. No shorty love. I always refer people back to this article. Thanks for taking the time to put this together.

  49. Nice caveat: This study does not aim to look at terminal effects, rates of drop and drift, combat effectiveness, ethical viewpoints, or legal/political issues.
    Increased barrel length does not mean a more accurate barrel. The benchrest crowd proved that years ago. So if accuracy is your primary concern, a moderately short barrel may be ideal.
    Basically it comes down to ergonomics – what works for you. You like a 16 inch barrel, then get one. You like shooting small targets at long range, get a longer barrel.
    What increased barrel length does add is more velocity, more energy, less drop, and less drift. Being a hunter, those are the factors that matter to me.

  50. This whole article and the following comments are quite possibly the largest collection of willful ignorance I’ve come across outside of random zombie forums. Outside of the 1 in 20 post that actually know what they’re talking about.

    Any approach at getting results being completely ruined by the massive amount of uncontrolled variables.

    Furthermore, this used only 1 type of round. This does not make it all inclusive for all rifles. Try shooting a .50 BMG round out of a 13″ barrel. Go ahead and cut that 300 win mag down to 16″. Lets see how much velocity you lose cutting down a 6mm barrel.

    There is no real “truth” to such a general topic and broad spectrum that encompasses firearms in this article.

    Sure, a shorter barrel is more rigid than a longer barrel. Congrats. You wasted all that time and energy “proving” something that has been explained ad nasuem by real shooters and barrel manufacturers.

    You should rename this to “I cherry picked my data to prove my point of view”. That is all this was. Most of the commenters should cancel their internet forever.

  51. I just bought my AR 15 Anderson 16 in Barl. Molly Lined 1 in 7 twist [ just wanted to know what was the twist rates on barells tested ? i think in all the readind i might have missed it. im shootin Hornday 40 gr sight in dead bulls eye 100 yrds. 200 yrsd 5 rounds in 2 in group . I think this is pretty Darn good right up there with my Savage Bolt .243 . I was planning on buyimg a longer barell for my AR but i think i will save some $ and just buy AMMO ;] Coyotes will be Howling RUN HIDEEEE

  52. The article had some good info, but in a nutshell it needs to be understood for most average shooters a longer barrel will be more accurate especially when shooting a pistol versus a rifle.. A 9mm carbine’s trajectory is easier to calculate then that of a 5 inch barreled 9mm pistol..

    The barrel length itself is only part of the factor because a .308 will go further with more power and less drop then a 5.56.. but because most people aren’t as good at instinctively calculating a bullet drop trajectory so even a difference of 300 fps can matter..

    Yeah I’ve seen guys who can shoot and hit a target at 400+ yards with a 9mm – because they practice and do it all the time.. but the average guy who shoots occasionally won’t be able to replicate this often..

    The “study” doesnt cover “IF” there is a tipping point. What if you cut a rifle barrel off to the length of 5 inches or 6 inches? Yes, I know thats not practical… but the point is you WON’T see the military or anyone else buying 6 inch rifles anytime in the forseeable future.. I’m sure the SEAL team & USMC Force Recon will stick with standard equipment because they need the extra 300+ FPS when using that longer barrel and shooting targets a 1/4 mile out and much further..

  53. A *lot* of info to absorb. This’ll require multiple readings.
    My takeaway: my 26″ 357mag levergun provides more mag capacity & that’s about it. I can live with that.
    Thanks y’all!

  54. Absolutely great article based on scientific fundamentals. Thank you for sharing. My passion for understanding ballistic science and the practical application thereof makes this fantastic reading. Wish I was closer to have been part of your research team. Thanx!!

  55. Interesting study. One thing to consider is longer barrels aren’t as stiff as a shorter barrels. Barrel profile also has an effect. A long skinny barrel is whippy, a heavy long barrel is less so. What that adds up to is a longer barrel provides a level of practical velocity (a velocity which kills quickly) which a shorter barrel can’t. So if you want excellent accuracy out of a long, heavy barrel which provides velocities which kill instantly, you need to find the accuracy velocity of that heavy, long barrel. There’s an article which explain this in great detail. See http://www.sportbar-favorit.ru/accuracy.html
    Best Regards

  56. In almost every data point in the nine accuracy graphs here the 26″ performed better than the 13.5″.

    So the claim that “There was no noticeable critical difference in accuracy at any range.” seems incongruous with the data.

  57. Thank God there was a link in your other article, to this one… So yeah… Have you started a blog yet? I think people should get more into the research and start questioning everything that they seem to know. Thanks for another great article.

  58. I thought Josh’s preconceived statements on barrel length, velocity and accuracy clearly depict common beliefs especially among surface readers and non-readers whom rely mostly on gun club banter. I’m sure we all understand a blog post is by no means a canvas for an all out research report. His work here does seem to predicate his thesis and I look forward to seeing more in-depth and expanded research on the topic in the future. Assuming the expense of any real world research in this area I’m looking forward to a crowd funded experiment in the coming years.

  59. To call this pile of juvenile word salad a study is a gross disservice to those in academia, government and industry that are doing actual real research. Just the space confirmation bias in this thing is enough to fill a galaxy. Asking a question that could not be possibly answered because the experiment wasn’t properly designed to do so is intellectual dishonesty or willful ignorance or borne of idealogical zeal. TTAG should be ashamed of promulgating this nonsense as information. At best the “study” results do not agree with the conclusions.

    • It is intriguing that “some dude” doesn’t give a real name… and yet he is claiming to have knowledge of higher “academia”. This is funny for two reasons. First, learn what an oxford comma is and when to use it. Second, don’t bash someone’s opinion then say the study dos not match the results when you give no hypothesis, synthesis, (notice the oxford comma I just used) or adjudication as to why the study is bogus. Who am I going to take more seriously? “Some dude” blabbing on a blog without any support or proof OR a company that obviously has money and the means to perform some testing and give results? If you want to be skeptical than at least suggest that it is worth looking into before you blast it without proof.

    • I hold three engineering degrees and I disagree with you. I thought the article was a very good start at using science to attempt to answer real world questions. BTW: since you invoke ‘academia”, what’s you academic background?

  60. Although interesting and compelling, the methods and the author’s conclusions are seriously flawed. A fifteen to thirty-one percent variance in data is not insignificant as the author claims. This author failed to employ the basic tenets of the scientific method, in which a problem is identified, relevant data are gathered, a hypothesis is formulated from these data, and most importantly, the hypothesis is empirically tested. This test is not science. The author failed to identified a standard and compare different conditions against that standard. If, for example the M80 ball, designated as a standard, was fired through barrels of different lengths and factory ammunition of different bullet weights were compared to this standard, this data might be valid. But by using ammunition from multiple manufactures and bullets types, to include hand-loaded ammunition, the author’s data is at best food for thought. In affect, the author has increased the volume of misinformation on this topic published on the internet.

    • you seem like a real smart and bold guy anonymously attacking a good author with a dry tone and stark opinions. why don’t you publish a report like this and see how seriously others take you. Sorry, but I’m just tired of trolls on this site. good day.

      • Actually, you are being sarcastic, naive or holding someones hand. This guy is correct and you should know that. I will give you an example. M855 was developed to shoot out of 20 inch barrels. It does ok out of 18 inch barrels. However, it doesn’t live up to the standard of piercing 1 side of a steel helmet at 600 meters with a 16 inch barrel.

  61. Yesterday I took my SAV 12 6MM BR NORMA out to the range, It has a 29″barrell and a 1in8 right hand twist. I shot two 4 shot groups , 0.1295″ and 0.1795″ at 100 yards. Admittedly I had refined the projectile seating depth. The first was on the lands and the second 20 thou off the lands. I was gobsmacked, never having shot that well at 100 yards with ANYTHING. The intervening groups were unremarkable at 5 thou intervals. Needless to say I gave her a cuddle when I cleaned her and put her away. I think it was the long barrel, low load of slow burning powder and Berger 105 grain VLD projectiles.

  62. I’ve read through this article and the comments a number of times. I appreciate both sides of the argument, and perhaps I should just leave it at that, but I feel compelled to say something.

    A lot of criticism is directed at the author for conducting a study that to many was not detailed or scientific enough. Yet in the same criticism, a great deal of weight is attached to wind without any mention of how much and from where. Yes I’m being pedantic, heavier and faster bullets will fair better in any wind than lighter, slower ones; but the point I am making is that surely in assessing “accuracy” or “precision” the notion of wind is meaningless. From a practical standpoint it is critical but in assessing whether a shorter or longer barrel is more accurate shouldn’t one be shooting in a wind tunnel to eliminate another external factor from the equation?

    I honestly don’t disagree with a lot of the comments made above, I have no dog in this fight, I don’t know Josh from Adam but I feel that some of the criticism is a little misguided. If you hunt, or wear a uniform I can appreciate that terminal effects downrange are similarly critical and it may be inadvisable to unnecessarily reduce bullet velocity where lives hang in the balance.

    That said, this study appears to show that a wide range of .308 ammunition (much of it not optimized for a particular barrel length) was shot out of barrels of varying length over various distances without a significant difference in accuracy.

    It was suggested that the same may well not be true of other calibres. I’ll subscribe fully to that theory. What these results do emphasize to me however is that the argument that the .308 calibre is extremely versatile is well founded. Whilst obviously the best results are obtained by optimizing barrel length and loads, what is apparent here is that even mismatching ammunition with barrel length produces credible results.

    Obviously building a 1000 yard gun with a 13.5″ barrel isn’t optimal but it is nice to know that with the advent of new firearms like Faxon’s ARAK 31 you could conceivably have a single rifle that serves as both an SBR with a sub 14 inch barrel and a longer range firearm with a 20 inch barrel and be able to expect decent accuracy over appropriate ranges irrespective of what ammunition is available.

    Of course that type of information is probably only relevant to people on Zombie Forums looking to build a bug out gun for which they can scavenge ammunition from any Walmart, Mom and Pop store or isolated farmhouse they come across …

  63. Very good article. Makes a good case for those who have bought a shorter barrel rifle but in the case of say an AR-15 there are some good reasons why people buy the 20″ barrel (the old mil spec length) instead of the shorter 14″-18″ barrels: 1) because of the longer barrel the gas pathway (for ejection) can be located farther down the barrel which results in lower gas pressure (and therefore presumably longer life) due to these lower pressures. On a shorter barrel, the gas port is located closer to the chamber meaning the gas is bled off at a much higher pressure with greater demands put on the system; 2) the recoil on a 20″ seems to be less than on a shorter barrel maybe because of more mass in the gun; 3) the bullet velocity is higher on a longer barrel and this results in a flatter trajectory. This is due to greater work applied to the bullet with work being the integral of PdV where P is pressure and dV is the change in volume. A greater barrel length has greater volume and hence more work is expended resulting in a higher velocity; 4) when using iron sights you get a better sight distance on a longer barrel. This is negated if you use a scope but for iron sights, the longer the distance between the sights the better the aim, in general and 5) the weight difference on an AR type weapon for a 16″ vs a 20″ barrel is a whopping 12 ounces (approx) out of about a 7 lb weapon. For these and other reasons, people elect to carry the slightly longer weapon.

    All in all though, you were spot-on with your information in showing that you don’t necessarily give up accuracy because of a shorter barrel but in the case of an AR, you do give up a number of things.

  64. 900 yds is not exactly the “Long Range” at which Long barrels become relevant now is it???
    Match shooters and Fclass go out to 1200 yds.. they do not mince about with anything less then 28″

    Try shooting a mile or a even just a kilometer with 308 out of that short barrel, then you might start to see some relevant data. I know guys that hit with great results at those ranges, but i can tell you they ain’t using 20″ barrels,they ain’t using 26″ either wich will get you to 1000 meters when a 20 won’t. And nevermind the 13″ Why are we even discussing this??

    • Why are we discussing this? Well, I think that is the comment of a narrow-minded person stuck in the old way of thinking. This article is extremely relevant to our interests as a community as SBRs and shorter rifles become the standard.
      I’ve shot a lot at longer ranges, and I’ll tell you that that represents only a small percentage of my actual shooting and hunting. I don’t think anyone would take an SBR out to hunt at 1200 yards, but there is literally no difference in anything out to about three hundred yards or meters. If you plug in the data and such for the 175 GGM, there isn’t even a real-world difference at that range, which makes a more compact rifle better for hunting in my mind. It’s already loud, so that’s not an issue.
      Also, I don’t think this article was written for people shooting F-Class. Your statement was kinda like posting about Formula 1 rules on a Neon mods site. I think it was written to show the normal shooter that he wasn’t losing anything by going shorter, which is all the rage these days. The whole 1000 yard benchmark is a bogus old way of trying to make rifles perform in ways that they weren’t meant to. There’s a reason the author of this article chose 900 yards as his limit, which if you read it you would know was as far as he could go, so I don’t know why you chose to make that an issue.
      Anyways, Van, ego is big when you sit behind a keyboard, but I bet you’d never cut up a barrel yourself and then take crap on the internet from know-it-all desk jockeys. The earth was flat once, just like all barrels had to be long. Times change, so try to keep up! If you read this, Josh, thanks and keep up the good work!

  65. I see a lot of hate on this article, but 175 or so comments spanning three years makes this one of the most traffic-rich and heavily debated articles on this site I’d bet. I found this while looking up a question about SBRs and this answered my question. I just can’t believe how narrow-minded most of the people in these comments are about what I think is a huge contribution to the community as a whole. I usually never comment on these boards, but the comments here are just incredible in their creative lack of vision. This is embarrassing, guys. A man going to college takes the effort to make a difference and honestly shows his results and you smear him with opinions stuck in the stone age? Seriously? This is how the gun community treats pioneers and trailblazers? You guys make me sick and I can see why the liberal left wants to disarm you. You can’t even be civil to your own people in your own press! Shame on you!

    Josh, if you read this, which I don’t know if you will, please take solace in the fact that your article has inspired a hundred shooters for every detractor in these comments. Shorter barrels and compact rifles are the way of the future and I’m sending my own 308 to be cut down to make it handier and lighter. Good work and please do more to rile up the neanderthals lurking in this community.

    Lonny H

    • Hey Lonny,

      I was an anthropology minor in college and, from what I learned, Neanderthal people were actually very intelligent and had a very long run in the timeline of human evolution. I wouldn’t think that they would be easy to rile up, as the fossil record demonstrates that they were expert craftsmen and hunters. http://www.bbc.com/news/science-environment-11408298
      Therefore, I believe that they would readily embrace new technology and be open to the ideas I presented here, unlike some members of Homo Sapiens Sapiens.

      Thank you for the support, Lonny. I’m glad I was able to help you out. Don’t worry about how this stuff is received by the community. They will learn eventually.


  66. Maybe I missed it, but where did you explain the hand load information? Unless you used specific burn rate powders for the different barrel lengths, ie: Slower burning for longer barrels I believe your tests and report are only valid for your specific burn rate of powder…
    Manufactured ammunition is generally manufactured as a good average for a specific caliber in a range of barrel lengths. Lets us your standard 308 Winchester X as an example. Put this is a typical 308 bolt action with a barrel length of 18-22 inches and will observe 1 MOA accuracy. Now take the same Ammo and it put it in a 26″ barrel and it shoots terrible! Why is this? It is because it wasn’t designed for that barrel length for optimum accuracy. Now go and buy a box of Supreme Hunting Ammo….More likely than not you will have the EXACT OPPOSITE results! it will perform under MOA in the 26″ barrel and shoot horrible from your run of the mill 18-22 inch barrel.
    Reloading is a science and you will find that taking ALL the recommended powders and loading with them for a specific gun the results will be similar…..Different powders are for different barrel lengths and burn rates. When I started reloading I would just select a power and load using all the proper techniques etc. I am getting much better now at picking a powder based on burn rate and the barrel length of the gun it is intended for. I have found that it is exponentially more accurate and takes much less time to work up a load. I would say when you have the right powder you can pretty much just load to whatever velocity you desire within spec and your results will be great! No more latter testing etc…
    This was a great article but in mypinion inconclusive for the intended purpose.

  67. This is an old post but was hoping someone would still be monitoring. As a qualified “Hoosier Hick”, who also has a Masters Degree, a fascination w statistics, and a job to match both, love empirical data and analysis. Maybe I missed it but I curious on some qualitative info, the complete experience-level of the shooter(s)? Does a longer barrel offer more stability for a more inexperienced shooter? For full disclosure, contemplating building a dual purpose AR-10 (tactical and hunting), as I own a couple AR-15’s but very much want to make an
    educated choice on barrel–which is my starting point.

  68. It seems to me you are referring to the variability of the rifle’s precision and not its accuracy. A rifle with a smaller SD of MOA in more precise than one with a greater MOA. One rifle with a ten inch group around a the point of aim point and another gun five inches around the same point are both accurate. One is more precise than the other.

  69. Interesting. Can’t say I am looking forward to sighting in a few new scopes I have just mounted after reading it. Earlier this year I purchased a break barrel airgun that was supposedly one of the better ones out there. When I tried to get a scope on it to zero though, it was all over the place. Finally, just to see, tried to see how it grouped with open sights at 25 feet. Still all over the place. Great to know info, add to that that some guns should just be sent back to their maker with a “Need refurbishing work” sticker on them for a big discount off of new for the next down ballot consumer.

  70. I often suspected these facts on short barrels to be true. But only had facts about velocity per inch lost when chopping a barrel. And when looking for evidence could only find armchair commandos very hostile opinions. Dont ask them anything unless you want to be virtually spit on and ridiculed. I honestly believe that alot of these people are kids and old ass wannabe people who are to dumb and lazy to do anything but watch youtube. So thank you very much for trying to prove you theory. And good luck with your schooling.

  71. I know you went to a lot of trouble for your data. Your test should have been conducted with 3 – 5 different rifles. Also when you load for a rifle you take in account the barrel length the bullet size the primer used how old the rifle is the cartridge and then you also lathe the cartridge thickness to even it out and trim the neck, deburr the primer pocket inside and out for the even flash, tumble the brass until it is clean inside and out, weighing and separating the cases and bullets into categories before reloading. A casing or (bullet) that weights slightly more than another means that it is thicker than the other hence it will hold the bullet with more pressure releasing the bullet with more pounds per square inch giving you the inaccurate grouping that you were getting. Doing these steps and more gives you the tighter grouping that you didn’t get in your results. You will also see the difference in accuracy from barrel lengths on distance shots. I reload for many people and when they shoot their grouping at 100 yards will fit in a dime.

  72. My lord what a long thread. We’ll said above. Was the rifle scrubbed clean before the test because if it was then you most deffinately introduced a climbing relative mv, lessening the mv loss with each chop. Your barrel would have been better to have dirtier up over 40 shots first.
    -I think you proved that velocity is vital to precision so yeah cheers for that. This made me buy a long barrel rather than a puny carbine that can only send light projectiles out to 100y ads. A slower bullet has to be lobbed up much higher to hit the same point. If there is wind, it gains a foot/second for every additional foot of elevation. That’s why the 308 is pathetic past 800m

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