What to Look For in a Custom Rifle – Chambers and Throats

In his next article on what to look for in a custom rifle, John Stewart of Kiote Corp explains the right way and the wrong ways to cut a chamber and throat for a rifle…

The number one problem with most rifles both factory rifle and also some custom rifles as well, is the manner in which the chamber is cut.

Factory guns are made with reamers that get used on hundreds and hundreds of chambers. Over time, the reamers become dull, chipped, and dimensionally smaller due to wear. Scoring, gouges, too loose, too tight are all problems commonly seen in factory and less quality custom guns.

Just recently, I was asked to correct problems with chambers on two rifles that you’d expect to be near flawless: one Kimber 84L and one GA Precision HRT rifle. Both exhibited excessive scoring caused by chips not being removed during the reaming process. Both exhibited longitudinal gouging caused by the reamer being forced into the chamber. These are irreconcilable errors on guns that the owners paid in excess of $3000 for.

When I cut a chamber, I never use a reamer that has been used on more than 4 other rifles. Once that reamer completes its fourth rifle, it either gets sent back for re-conditioning or it gets tossed in the recycling bin. This ensures that my tooling is sharp and dimensionally sound before it ever cuts steel.

I also never cut more than 0.010” in depth in one pass. This ensures that I’m not overheating my tooling Even with oil or coolant applied, heat is generated which creates problems. More importantly, this ensures that I don’t have excessive chip build-up which could cause scoring or gouging inside the chamber while it’s being cut.

300 Norma Mag Chamber Cut Before Oil Removal and Honing (image courtesy of Kiote Corp)

My lathe does not have integrated coolant nozzles. Even if it did, it wouldn’t really work for chambering because I don’t want to push/flush chips into the chamber. I’ve found that using ISO 32 machine oil on my tooling allows for both proper cutting and ease of chip removal during the cut, allowing the chips to slide down the flutes of the reamer and out of the chamber. I also use a floating reamer holder from Manson Precision that ensures that my reamer stays inline and parallel with the bore. Even if my barrel were to be a half-thousandths out, the chamber would still be cut properly.

Once I’ve achieved proper headspace, I use a honing brush from Flex-Hone to ensure a near-mirror finish on my chamber walls. I don’t necessarily believe that a true mirror finish is necessary. In fact, I prefer not to have one because the walls should provide a slight resistance to the brass during expansion so that everything stays in line with the bore during the burn process of firing.

Properly cut and throated chamber after 1,000 rounds. (Image courtesy of Kiote Corp)

Another problem is that all factory rifles are chambered with a long throat. This is primarily done to ensure that no matter what brand of ammo the consumer is using, it will fit in their rifle. While it’s convenient, it’s also detrimental to both accuracy and life-expectancy.

Factory cut chamber after 1,000 rounds. (photo courtesy of Kiote Corp)

The longer the jump is between the ogive of the projectile to the start of the bore, commonly known as “free bore”, the bigger the chance is for that projectile to get off-center, commonly referred to as “sideways”, before entering the barrel. This is exaggerated by out of square, off-center chamber cuts commonly seen in most rifles.
The long throat also allows for quicker throat erosion. With the projectile essentially banging against the throat of the bore, it erodes microscopic pieces of the metal with forces in excess of 40K PSI found in most center fire rifles used for hunting or competition.

Several well-known custom have led the consumer to believe that they are required to have a longer throated chamber now so that they can set the projectile out farther to achieve greater velocity. Time and time again, history has proven that most calibers are more accurate and have longer life expectancy by setting the projectile a specified length off of the lands, typically 10-20 thousandths of an inch.

comments

  1. avatar Ryan says:

    With the longer-throated chambers, you’re still setting your projectile’s ogive 0.010-0.020″ from the lands, but with more volume in the boiler room of the case. This also allows you to run the longer, heavier, higher BC bullets without taking up case volume.

    None of this necessarily improves pure accuracy, but allows for more case volume and thus more velocity. In a Palma rifle, for example, you need all the case capacity you can get to cram more powder behind a .308 projectile. It needs all the help it can get to make it to 1000 yards without getting blown out of the 10 ring by a 1 mph wind gust or switch.

    It’s all a compromise…. magazine length restrictions, case capacity, velocity, projectile selection.

    1. avatar NoMore says:

      Yep. And those longer, heavier bullets and faster twist rates all eat up that “space in the boiler room” by requiring larger quantities of slower powders that typically exceed significantly what the case and primer are capable of reliably and efficiently using. Then there are the issues with “copper fouling” that supposedly are “no big deal” to “long range shooters” but signify real problems with gun and/or ammunition or both to everybody who has been shooting since before Obama’s first term. The same “gun experts” seem to regard “pressure signs” as some sort of “tuning tool” rather than the genuine red flag significant warning signs of VERY overpressure “loads” that they actually are given the fact that they really only start ABOVE the “proof pressure” of commercial cartridges/components/guns since PROOFING a gun/cartridge requires both the gun and cartridge cases post-proof to show no “external signs” that an “overpressure” cartridge was fired. That means no flattened primers, no sticky bolts, no “ejector marks” (actually caused by the ejector BORE as brass in the “thickest” and “strongest” and “heaviest” part of the case “flows” into that BORE) and no other “pressure signs”. Since most proof loads/pressures are “max” plus 10% and most guns/components have to safely “proof” at the highest pressures achievable by the “hottest” cartridges they’re capable of chambering from the factory, that means up to 70,000 psi for high-powered rifles. When you see pressure signs that means you’re well OVER 70,000 psi and literally are in “uncharted territory”. But “gun experts” who seem to think manufacturers and “factories” and professionals who have been “into guns” longer than they’ve been alive several times over in many cases are all “clueless” just go on about doing and saying stupid shit like you just did. Hopefully they’re the “shooters” behind the trigger when “pressure signs” turn into “catastrophic failure” and nobody else gets maimed/killed. I’d say hopefully NOBODY is behind the trigger when that happens but somebody has to be and they sure as fuck aren’t smart enough to learn anything before deciding they’re “experts”.

  2. avatar Joe R. says:

    “Irreconcilable” as in no-can-fix those screw-ups (without a new barrel)?

    I know mr. Coyote is not really responding here, if anyone knows the answer i’ll pay in “TTAG-coin”, my newly minted crypto-currency of the Realm.

    /sarc [wink, meet me on the dark web]

    P.S.
    I bet those cut-in-half chambers are loud as hell (for a few milli-seconds).

    1. avatar Joe says:

      P.P.S.

      Don’tcha just hate when somebody comes along and makes you think you need to upgrade something?

    2. avatar Dyspeptic Gunsmith says:

      Yes, it would take a new barrel. There are only two ways to fix the sort of problems Mr. Stewart is referencing there:

      1. Put on a new barrel, and then profile the barrel to match the inletting on the stock.
      2. You could “set the barrel back by a turn,” ie, you move the barrel shoulder forward by one turn, decrease the length of the tenon by that one turn, extend the threads forward by one turn, and then deepen the chamber to a point where you can close a stripped bolt on a “go” gage. The problem with doing this is that the barrel’s taper will no longer match the inletting, and you basically need a new stock.

      Now you understand why so many match barrels, where shooters do set their barrels back by a turn, don’t have a taper on the barrel; when you set them back, nothing about the inletting changes.

      1. avatar J says:

        Ummm…..no…?

        Unless your barrel is reverse-tapered, and/or full-length bedded (a fashion that thankfully died with the ’60s), setting your barrel back will only add a little clearance to the float, or change where the forend’s pressure point contacts the barrel – not a problem, in either case. Setting a x/16 thread barrel back 1/16″ of an inch, the taper shift will only change the diameter of the barrel at any point in the inlet by a few 0.001″. Float is float, whether you have 0.010″, or no forend at all.

        Also, this has nothing to do with why “match” barrels are often not tapered. If a match barrel is not tapered, it’s because the match rules allow it, and a non-tapered barrel generally performs better, where allowed.

        I know it’s fun to say things, but you really should think about them before you do.

        1. avatar Dyspeptic Gunsmith says:

          I take it you’ve set back barrels in a high-dollar stock then?

          When I say “high dollar,” I mean stocks where the walnut cost about a $K, never mind the cost of the finished stock, and the owner paid for the barrel inletting to have barely any clearance…

        2. avatar J says:

          Yes. I have.

          By the time a client had put enough rounds through their custom rifle that it was ready for a set-back, they were willing to accept a float going from 0.010″ to 0.015 or 0.020″. If the rifle was set up with a pressure point, I’d sometimes have to build that back up with glass, but not always.

          But, of course, the topic being discussed, chiefly, is precision rifles, which are usually stocked in something other than wood, and, as of late, painted some sandbox-ninja color, so it’s a non-issue.

          I notice your reply had nothing to do with your bunk comment about “why match barrels have no taper”, though.

  3. avatar MiserableBastard says:

    I watched the first 2 or 3 minutes of a bond arms show (turned out to be a 30 minute commercial). In the first minute or so, there was a montage of notable people holding a Bond Arms derringer. One of the pictures was of TTAG Resident war hero Jon Wayne Taylor. Oh, Former Texas Governor Rick Perry was also in the picture 🙂

  4. avatar Dyspeptic Gunsmith says:

    I agree with most everything here, especially Mr. Stewart’s practice of using a reamer for only four chamberings before sending it out for re-sharpening, or putting it aside to be used as a roughing reamer or something else (ie, recycling the HSS for some other tool). For higher-use chambering, I might spring for a carbide reamer; they hold their sharpness longer. Most all of my reamers are live-pilot reamers, which I prefer over the older-fashioned stub pilot reamers.

    In my shop, I like using high-sulphur cutting oil when I’m cutting chambers or other similar operations. I too cut only 0.010 to 0.015″ depth at a pass. Mr. Stewart didn’t say how he rough-cuts the chambers (to remove the vast majority of the material before using the finish reamer). I tend to not use roughing reamers (which are ground/sized to cut an “undersized” chamber, allowing perhaps no more than about 0.015″ that the finish reamer needs to cut. I use a twist drill, judiciously applied, and then a boring bar to clean up the hole to be round, concentric with the bore axis and have the majority of the case taper cut.

    One of these days, I’ll sink some money into Greg Tannel’s through-the-bore chamber flushing setup, which uses a hydraulic pump and a special hydraulic fitting on what would be the muzzle of the barrel, to push cutting lube up the bore and the chips out of the chamber, up towards the tailstock of the lathe. It’s a bit of a bother to build up and to set up, but it saves a bunch of time during the actual chambering, because you don’t need to cut in 0.010 to 0.015″ depth steps – you just make sure your reamer is clean and sharp, put it into the bore, start the high pressure lube pump, and then start cutting. The chips come out of the chamber over the end of the reamer. You might need to use live pilot reamers that have little notches cut into the pilot bushing to get the lube to flow over the pilot effectively, tho.

    The free-floating reamer holder. There is probably more debate over this issue in chambering rifles than most anything else. Some people swear you need them, some swear you don’t, some people use them and swear at them. I know of the type of floating reamer holder Mr. Stewart is using, and it is a good one. I’m in the camp of “I like that type of reamer holder, until I get a chamber that starts to chatter… and then I don’t like them.” There’s an alternative reamer holder called the “Bald Eagle” type of reamer holder, where the reamer isn’t held as it is in Dave Manson’s reamer holder. With the Bald Eagle type of reamer holder, if the reamer “grabs up,” I just let go of the handle and the reamer spins with the barrel, and the chatter stops immediately, faster than it would if I hit the brake on the lathe. I then stop the lathe, and then I start cleaning things up, re-lubing, etc, looking for the cause of the chatter. Sometimes, it’s just the barrel steel, and there’s not much I can do, other than put a shop towel over the reamer before I send it in, or I change spindle speeds, etc.

    Here’s a pic of Dave Manson’s reamer holder:

    https://i0.wp.com/rifleshooter.com/wp-content/uploads/2015/02/12-bolt-nose-recess-set-up.jpg?ssl=1

    Here’s a pic of the Bald Eagle reamer holder:

    http://pacifictoolandgauge.com/reamer-holders-arbors/112-bald-eagle-floating-reamer-holder.html

    As I said, they both work. To me, the nice thing about the Bald Eagle style reamer holder is that when things start to go wrong, I can literally feel it through that handle w/ the knob. If I’m not holding onto that knobbed handle, the reamer won’t cut in the barrel – it will just spin on the pilot mandrel that’s mounted in the tailstock. As soon as I feel something start to go awry, I let go and then stop the lathe.

    Only a couple of other things on the subject of throats, etc. The high-precision guys are increasingly preferring chambers with under-sized necks, which allow them to “neck turn” their brass in a little widget that looks like this:

    https://www.brownells.com/userdocs/products/p_749006477_1.jpg

    The idea is that by turning the neck brass with a pilot inside the neck of the bullet’s diameter, you get the brass thickness of the neck truly uniform, all the way around. The object of this entire exercise, starting with shortening up the throat, under-sizing the neck of the chamber, turning the case necks to get them truly concentric, etc – is to get the bullet launched out of the case and into the bore perfectly on the axis of the bore, so that the bullet does get “bobbled” or deformed from one side to another, and a high quality, non-deformed bullet (eg, start with a Berger/Barnes/etc all-copper, match VLD pill) should be turning perfectly on its long axis, with as little runout and precession as possible, thereby reducing group size downrange.

    PTG can supply “undersize neck” reamers in some of the chambers more commonly used in precision shooting:

    http://pacifictoolandgauge.com/6mm-635mm-nopix-showcart-/11059-6mm-br-order-any-oal-freebore-neck.html

    6mm BR is one of the cartridges used by the benchrest community for decades, and the basis for much experimentation in rifle accuracy/precision over the years.

    Enough of my prattle here. This is a subject where, if we collected a half-dozen gunsmiths together over a bottle of whiskey, we’d arrive at 14 different opinions on the matter in one evening.

    1. avatar NoMore says:

      You’d have to find half a dozen actual “gunsmiths” rather than half a dozen “gunsmithing school graduates/former apprentices” that don’t generally know shit from apple butter when it comes to guns and demonstrate it in every online blog post/comment/YouTube video where they hold forth on the “right” way to “build rifles” and what to do to “fix” all the “fuckups” companies/people that have been making rifles since before their great grandpappy (or “master” or “instructor” even) were born make when they still can’t get it “right” lo these many, many decades to over a century later.

      And good luck finding half a dozen real gunsmiths willing to sit around and argue about whether or not a bunch of blowhard fucktard “gun experts” online are “right” or “wrong” and willing to “talk shop” in the far smaller amounts of “free time” true professional tradesmen actually have compared to the online “experts” that seem to have plenty of it as they sit in their empty “shops” making “how-to” videos, blog posts, comments etc with nary a customer visit or phone call to interrupt them.

      That you think they’d all be “whiskey drinkers” by default shows how “intelligent” and “open-minded” you really are when it comes to “professionals” in the technical trades you apparently assume are all…like you and your “gunsmith”. “Whiskey” tends to be for drunks and white-collar “intellectuals” who have plenty of time to sit in bars (private or public) pontificating on things like the opinions of others while most technical trades guys (at least the hundreds I’ve worked with coming from a wide variety of trades) tend to gravitate more towards a cold beer.

      That’s not so say that none of them enjoy a mixed drink of “whiskey” straight up but guys that work for a living and particularly with their hands kind of like something quick and easy for rest and relaxation with adult beverages at the end of the day. And beer cans/bottles are much easier emptied and disposed of in the “shop” than a whiskey bottle. Having a bottle stashed at work between post-work “cocktails” has been the ruin of plenty of “working” men and women and I think probably more “white collar” types than “blue collar” types. Those stashed bottles are also an open invitation for “visitors” who always seem to show up at quitting time to continue to show up at quitting time whether “invited” or not whereas cold beer can’t really be counted on to be there a few days or a week later. And those visitors are usually white-collar pains in the ass who like to show up where people work for a living, drink their booze, go home half in the bag and then blame those bastards “down at the shop” for getting them drunk when they catch hell from their mommy/wife/girlfriend and they usually claim they only stopped by for some “business”.

      Next thing you know, the hard-working blue collar guys “down at the shop” are asshole drunks getting shitfaced every night every time somebody needs an excuse for why they or their child/hubby/boyfriend came home hammered again, the bullshit story spreads, somebody runs their mouth around the “authorities”, they take an interest in the “partying” at whatever business after-hours and eventually somebody besides the white collar pain in the ass who can’t buy his own damned booze and drink it at home like a real man gets pulled over leaving “work” and shit goes to hell in general all because some white-collar whiskey drinking tightass mooching bum didn’t have the stones to buy his own bottle and didn’t want to go home to the old lady sober repeatedly.

      Or somebody who works there gets “busted” by HIS old lady when word finally gets around to HER that once in a while there’s a big “party” at the shop after work. And either way, lives get all fucked up and all because white-collar “professionals” like to hang around and drink other people’s booze on other people’s property when they don’t want to go home to their old ladies and instead want to sit around “debating” bullshit nobody else gives even two fucks about and don’t listen too anyway. All because whiskey and real jobs just don’t mix that well.

  5. avatar Slow Joe Crow says:

    The guy at rifleshooter.com has a lot of articles on barrels, chambers and receiver tuning since he builds custom rifles. Well worth a look to see how it’s done.

  6. avatar James Ivy says:

    My Ruger American ranch in 5.56 has an extremely long jump I feel, if I load a 75gr A-max at 2.580 that’s .002″ off the lands that’s a long jump for normal ammunition, but it doesn’t shoot any better than my 60gr A-max seated to the recommended length so go figure

    1. avatar NoMore says:

      I’m fairly certain the just like the “factories” know a hell of a lot more about “building rifles” than the average “gunsmith” these days, a “factory” like Ruger also knows how the hell to chamber its barrels properly. The thing about “heavy” long-for-caliber bullets like all .224″ bullets over 70 grains is that they don’t just ADD LENGTH AND WEIGHT “UP FRONT”. IT HAS TO BE ADDED “EQUALLY” AT BOTH ENDS AND THERE”S MORE TO HOW FAR/LONG THE “JUMP” IS THAN JUST “COL”.

      ESPECIALLY WHEN THE “COL” BEING CITED AS AN EXAMPLE IS SIGNIFICANTLY “OUT OF SPEC” COMPARED TO THE CARTRIDGES “OFFICIAL” MAXIMUM COL. WHICH IS THE CASE WITH YOUR EXAMPLE. AND THERE REALLY ISN’T A “JUMP” AS LONG AS THE BULLET “BEARING SURFACE” ENGAGES THE “LANDS” BEFORE THE “TAIL” OF THE BULLET CLEARS THE CASE MOUTH. WHICH IS ESSENTIALLY ALWAYS THE CASE UNLESS YOU “GUNSMITH” WANNABES COME UP WITH SOME SUPER-DUPER “WILDCAT” CARTRIDGE LOADED WITH SOME STUPIDLY LONG FOR CALIBER BUT SHORT FOR BEARING SURFACE “SUPER BULLET” SO THE “FREEBORE” IS LONGER THAN THE “BULLET BEARING SURFACE LENGTH”. OF COURSE THERE ARE NO “SAAMI” OR ANY OTHER KIND OF “SPECS” FOR THOSE “WILDCATS” BEYOND WHAT THE “WILDCATTER” ENDS UP “MEASURING” ONCE HE FINDS SOMEBODY TO MAKE A “CUSTOM REAMER” FOR HIS “WILDCAT” THAT HAS “SPECS” HE PULLED RIGHT OUT OF HIS ASS AND WROTE DOWN ON A NAPKIN OR SOMETHING.

      YOUR OWN “WILDCAT” 75-GRAIN A-MAX “5.56” LOAD (THERE’S NO SUCH THING AS A “5.56” RELOAD OR HANDLOAD SINCE THERE ARE NO “5.56” RELOADING DIES, GENIUS – THEY’RE ALL “.223 REMINGTON” REGARDLESS OF WHAT THE HEADSTAMP AND/OR YOUR BARREL/RIFLE HAVE STAMPED ON THEM, BY THE WAY) IS COMPLETE IRRELEVANT JUST LIKE YOUR “FEELINGS” ON WHETHER OR NOT THE “JUMP” IN A RUGER RIFLE CHAMBERED TO “SAAMI SPECS” ARE BECAUSE YOU CHOOSE TO LOAD A “WILDCAT” DESPITE THERE BEING OTHER “HEAVY” .224-CALIBER BULLETS THAT CAN AND WILL FIT IN A STANDARD MAX COL “5.56” CARTRIDGE AT 2.250″ COL.

      AS FOR YOUR “FEELINGS” THEMSELVES, THEY’RE TYPICAL WANNABE GUNSMITH DRIVEL AND COMPLETE BALLISTIC BULLSHIT. THE “FREEBORE” OF A “THROAT” IS NOT THE SAME ID AS THE ACTUAL “BORE” OF THE BARREL ITSELF AND THE “JUMP” DOESN’T EXIST ANYWHERE BUT THE MINDS OF YOU WANNABE GUNSMITHS THAT DON’T “GET” THE DIFFERENCE BETWEEN “CHAMBER” AND “THROAT” AND “BORE”. YOU THINK YOU’RE DOING SOMETHING “SPECIAL” WITH THOSE FACTORY-MADE “HEAVY” BULLETS SEATED OUT STUPIDLY FAR TO AVOID “JUMP” JUST LIKE YOU THINK “MINIMUM” NECK TENSION AND “EASY” BOLT OPERATION ARE “GOOD THINGS” FOR “ACCURACY” AND “PRECISION” INSTEAD OF EXACTLY THE OPPOSITE. WHICH IS WHY YOU ALSO THINK “SUB-MOA” IS “IMPRESSIVE” WITH YOUR “PRECISION” LOADS AND RIFLES AND OTHER HARDWARE IN A DAY AND AGE WHEN “SUB-MOA” IS PRETTY MUCH EXPECTED FROM QUALITY RIFLES, AMMUNITION AND COMPONENTS BECAUSE THEY’RE…RIFLED. AND ITS “GUARANTEED” BY PLENTY OF MANUFACTURERS OF BOTH “HIGH-END” AND “ENTRY LEVEL” SEMI-AUTO AND BOLT-ACTION “SPORTING RIFLES”.

      HELL, I’VE GOT A LES BAER 1911 IN .45 ACP THAT’S “GUARANTEED” TO SHOOT 1.5″ GROUPS AT 50 YARDS AND IT’LL DO IT EVEN WITH “EL CHEAPO” RELOADS I THROW TOGETHER WITH MY OWN CAST LEAD 200-GRAIN SWC BULLETS AND A LITTLE BIT OF TIME AND CARE “PRECISION” LOADING THAT “VARMINT AMMO” WITH A BEAT UP OLD SET OF LEE DIES I GOT ALONG WITH A BUNCH OF OTHER ODDS AND ENDS INCLUDING SEVERAL POUNDS OF POWDER, A COUPLE POWDER MEASURES ETC FOR $75. I USE THOSE FOR MY .45 ACP AND .460 ROWLAND “VARMINT” AND “DEFENSIVE” AND “TARGET” AMMO SO I CAN LEAVE MY “NEW” LEE .45 DIE SET IN MY DEDICATED DILLON 550 .45 ACP TOOL HEAD.

      I’VE GOT A 25-YEAR-OLD BROWNING A-BOLT STAINLESS STALKER IN .30-06 I BOUGHT BRAND-NEW THAT A FEW WEEKS AGO WOULD HAVE SHOT A SUB-.75 MOA 5-ROUND GROUP IF I HADN’T SPOILED IT WITH A 3RD-ROUND “FLYER” THAT STILL STAYED CLOSE ENOUGH TO THE “ONE RAGGED HOLE” 1ST, 2ND, 4TH AND 5TH ROUNDS TO BE A “1 MOA” GROUP. AND THAT WAS WITH 110-GRAIN V-MAXES. MY “HOMEBUILT” AR IN “5.56” WITH A WILSON COMBAT 18″ “MATCH” STAINLESS BARREL, TIMNEY TRIGGER AND MAINLY PSA PARTS IN A GOOD LOWER AND UPPER I’VE GOT ALL OF $1200 IN CAN, WILL AND HAS PUT 10 ROUNDS IN 1 INCH AT 100 YARDS AND I’M SO FAR FROM A “BENCHREST” SHOOTER IT ISN’T EVEN FUNNY. ONE OF THOSE GROUPS WAS OVER MY PICKUP HOOD IN A GRAVEL PIT AND THE OTHER FROM AN ACTUAL “BENCHREST” USING NOTHING BUT BEAN BAGS FOR THE REST. AND ONCE AGAIN, THAT’S WITH PLAIN OLD HORNADY V-MAXES. IT DOESN’T CARE IF THEY’RE 40-GRAIN, 50-GRAIN OR 55-GRAIN. I GET 3300 FPS MV (WITH A REAL CHRONOGRAPH RATHER THAN A MAGNETIC OR RADAR “JOKEOGRAPH”) WITH 40s and 3100 with 55s. AT LEAST A FEW THOUSAND ABSOLUTELY TROUBLE-FREE ROUNDS AND A BIG PILE OF PRAIRIE DOGS LATER, IT SHOOTS AS WELL IF NOT BETTER TODAY THAN WHEN “BRAND NEW”. AND IT DOESN’T DO THAT SUPPOSEDLY “BENEFICIAL” COPPER-FOULING BULLSHIT EITHER. EVER. NONE OF MY RIFLES DO WITHOUT ME WONDERING AND THEN FIGURING OUT WHY AND THEN FIXING THE “PROBLEM”. ANY BARREL THAT HAS TO BE “FOULED” TO SHOOT “WELL” IS A PIECE OF SHIT BARREL REGARDLESS OF WHO “MADE” IT.

      AS FOR ALL THE CRAP ABOUT “JUMP” AND “FREEBORE” AND SEATING BULLETS “OFF THE LANDS” X “THOU”, THAT’S JUST MORE HILARITY FROM THE BANDWAGON “GUNSMITH” WANNABE CROWD. I LAUGH MY ASS OFF AT THE CONTINUOUSLY REPEATED WANNABE “GUNSMITH” IDEA/THOUGHT/CONVENTIONAL WISDOM THAT THE “LANDS” ARE ANYTHING BUT THE “LEFTOVER BORE” AFTER THE GROOVES ARE CUT LIKE THEY’RE SOME KIND OF “BARRIER” OR “OBSTRUCTION” STICKING OUT IN THE BORE OR SOMETHING RATHER THAN JUST WHERE THE ACTUAL BORE STARTS FORWARD OF THE “OVERBORE” OR “FREEBORE” OF THE THROAT.

      THE BULLET HITS THE “LANDS” BECAUSE ITS “OVERSIZE” RELATIVE TO THE BORE. NOT BECAUSE THE “LANDS” ARE “UNDERSIZE” RELATIVE TO THE BULLET DIAMETER. AND SINCE THAT BULLET IS OVERSIZE BY SEVERAL “THOU”, ITS FUCKING IMPOSSIBLE FOR THE BULLET TO BE THROUGH THE “FREEBORE” AND STILL “OFF THE LANDS” A FEW THOUSANDTHS EVEN IF YOU “PRECISION SHOOTERS” WERE ABLE TO HOLD THAT KIND OF “CONSISTENCY” WITH PLASTIC-TIPPED BULLETS OR ANY OTHER BULLETS THAT WILL EASILY VARY IN “LENGTH” BY A FEW “THOU” AND WHEN THOSE BULLETS ARE INSTALLED IN “WILDCAT” OVER-MAX-COL CARTRIDGES THAT WON’T EVEN FIT IN A FREAKING MAGAZINE AND SURE AS HELL AREN’T SEATED “FULLY” SO THE ENTIRE “BEARING SURFACE” IS INSIDE THE NECK/CASE.

      AND THE “FREEBORE” – WHICH IS THERE PRIMARILY SO THE CASE NECK HAS ROOM TO “EXPAND” SO THE BULLET IS “RELEASED” – IS “REDUCED” DOWN TO THE ACTUAL “BORE DIAMETER” WHERE THE “LANDS” START. THE “LANDS” BEGIN WHERE THE “GROOVES” BEGIN AND WHERE THE “FREEBORE” ENDS AND IF YOU THINK THE “JUMP” MATTERS AS LONG AS THE BEARING SURFACE “HITS THE LAND” BEFORE IT CLEARS THE CASE NECK/MOUTH, YOU’RE PROBABLY A WANNABE “GUNSMITH” AND/OR “BALLISTICIAN” THAT ISN’T EVEN SMART ENOUGH TO LOAD “PRECISION” AMMO TO EVEN THE MANUFACTURER’S “OUT OF SPEC” MAXIMUM COL FOR A GIVEN BULLET.

      YOUR “LOADS” ARE DAMN NEAR .200″ LONGER THAN HORNADY LISTS FOR “75-GRAIN A-MAXES” IN THE HORNADY RELOADING MANUAL. THEIR DATA SHOWS 2.390″ AND YOU’RE CLAIMING 2.580″. SO WHO IN THE FUCK IS MAKING SHIT UP AS HE GOES ALONG AND WHO PROBABLY KNOWS HOW TO BUILD RIFLES, AMMUNITION, COMPONENTS ETC PROPERLY FOR MAXIMUM ACCURACY AND PRECISION? MY MONEY IS ON RUGER AND HORNADY, WANNABE.

  7. avatar Steve says:

    For the sake of the discussion, exactly what is your definition of a “long” freebore? I’m at a loss how a bullet can be “banging against the side of the throat” unless the bullet has completely left the neck of the round, the chamber is cut so far out that it’s dangerous, and whoever loaded them never checked the case nor the load with concentric measuring gauges.

    While I REALIZE this is about long range, precision rifles, the entire throat issue is of interest to me. I’m at a loss how a so called “properly” throated round can shoot great, but so do many rounds that used CIP specs and can have no freebore and as much as 1.10 inches of lead. When BOTH shoot 3/4 MOA with proper loads, both are getting velocities at the upper levels of the round’s expected levels (and not wimpy at all)………I’m ready to toss it all out the window and just throat my wildcat long enough to use any bullet I may use. (Hunting purposes).

    1. avatar NoMore says:

      Don’t confuse the “experts”. They don’t get that “freebore” and the “jump” are completely irrelevant as long as the bullet bearing surface “hits the lands” – which are nothing but the “regular bore” (non-free bore?) minus the “grooves” cut into that bore – before that same bullet bearing surface clears the neck/case mouth. They picture bullets actually “banging around” in that “freebore” even though the “freebore” of the throat in “commercial” cartridges made to “SAAMI SPEC” will A) only be the “inside diameter” to allow a “slip fit” of the “outside diameter” of the bullet which is “oversize” for the actual BORE “across the lands” and B) is only there so PROPERLY “LOADED” AMMUNITION WITH THE COMPONENTS AND VARIOUS DIMENSIONS BEING CORRECT BY “SAAMI SPEC” HAS ROOM FOR THE NECK TO EXPAND TO “RELEASE” THE BULLET and C) will always be “shorter” than the bearing surface of the shortest “commercial” bullet available in that cartridge’s caliber at the time the “SAAMI specs” ARE DETERMINED minus a significant “safety factor” in case somebody does the unthinkable and comes up with a LIGHTER AND CHEAPER AND SHORTER AND MORE CONSISTENT BULLET DESIGN.

      THE “EXPERTS” CLAIM TO BE ALL ABOUT “ACCURACY” AND “PRECISION” BUT YET END UP WITH “PRECISION AMMUNITION” THAT’S TOO LONG TO FIT IN A “SAAMI-SPEC” CHAMBER/THROAT/MAGAZINE AND WON’T EVEN “CHAMBER” PERIOD UNLESS THEY “CUT DOWN” THE OD OF THE NECKS BECAUSE THE “GENIUSES” REFUSE TO “DAMAGE” THEIR “ACCURACY AND PRECISION” BY “FULL-LENGTH SIZING” THEIR BRASS. THAT THEY ONLY GET 4-5 RELOADS “MAX” AND FOR SOME REASON NEED TO TO “FIRE FORM” BRAND-NEW CASES SUPPOSEDLY MADE PRECISELY FOR A GIVEN “COMMERCIAL” CHAMBER AND AREN’T SMART ENOUGH TO “GET” THAT BOLTS AREN’T SUPPOSED TO “FLICK OPEN” AND “FALL CLOSED” AND DON’T IN GOOD RIFLES LOADED WITH QUALITY AMMUNITION PROPERLY LOADED TO “SAAMI SPECS” AND ARE ALL ABOUT TELLING THE REST OF US “NON-PRECISION SHOOTERS” HOW THE FUCK TO GET “SUB-MOA” ACCURACY/PRECISION OUT OF “CUSTOM” RIFLES/CHAMBERS/THROATS/CARTRIDGE DIMENSIONS WHEN MOST OF US “NON-PRECISION” SHOOTERS PRETTY MUCH EXPECT THAT KIND OF ACCURACY/PRECISION AS LONG AS QUALITY HARDWARE IS USED. ESPECIALLY SINCE $400 “BUDGET” MASS-PRODUCED RIFLE/OPTIC COMBOS THEY LOOK DOWN THEIR PRECISION NOSES AT OFTEN COME WITH “SUB-MOA” ACCURACY GUARANTEES THESE DAYS WITH NO STRINGS ATTACHED AND NO REQUIREMENTS FOR “PRECISION LOADED AMMUNITION” AT ALL. IN FACT, SINCE MOST “MASS PRODUCERS” OF “FACTORY” (THEIR “HIGH-END” PARTS AND COMPONENTS AND OTHER HARDWARE IS ALL HAND-MADE BY AGED, EXPERT “CRAFTSMEN” AND NOT IN “FACTORIES” APPARENTLY) RIFLES ARE ALSO IN SOME WAY, SHAPE OR FORM ALSO IN THE “AMMUNITION BUSINESS”, THEY SORT OF PREFER THAT “FACTORY AMMO” BE USED TO DEMONSTRATE THAT YOU DON’T HAVE TO BE AN “EXPERT” IN “BALLISTICS” AND “CUSTOM RIFLES” AND “PRECISION AMMUNITION” TO BE A “SUB-MOA SHOOTER”.

      LIKE I SAID, DON’T CONFUSE THE “EXPERTS”. THEY EXIST IN A PARALLEL UNIVERSE WHERE “SKILL” IS FOR SALE EVEN IF THEY NEVER MANAGE TO FIND THE “STORE” SELLING IT.

  8. avatar NoMore says:

    Boy, if you don’t know that a REAMER is not a “drill bit” or “boring tool”, there’s not a hell of a lot of hope for you ever managing to get more than “4 rifles” out of a reamer before it needs “reconditioned”. And if you think its POSSIBLE to “recondition” a REAMER by “grinding” or otherwise removing metal from it besides “reconditioning” it down to a SMALLER CARTRIDGE/CHAMBER, there’s even less hope for you. Where did you go to “gunsmith school” and how many cereal box tops did your “degree” cost you?

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