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I’ve been drinking the 300 BLK Kool Aid for a while now, and one of the reasons is that even though the factory fresh ammo is scarce I can cook up as much as I want from old 5.56 brass and readily available components. I’ve recently had a number of people ask me for my particular recipe (the combination of components and powder weights that make my load), and I figured it would be a good idea to put that into article form so I can talk a little about why I chose the components I did and how I got to my current load.

First things first: a standard disclaimer. Reloading ammunition is an inherently risky activity. This load works for me, but I CANNOT guarantee that this load won’t blow up your gun and/or kill you. I highly suggest you start with a lower load and work your way up as you become comfortable. Use this load at your own risk.

Enough stalling, here’s the recipe:

Powder Hogdon H110
Primer CCI #400
Bullet Type Hornady FMJ BT
Bullet Wt 150 gr
Powder Wt 16.5 gr
COL 2.260 in

Experienced loaders will notice that I’m using a pistol powder for a rifle load. Which, normally, is a big no-no as pistol powders burn much too fast. But since there’s really almost no case volume left in the 5.56 case once you cram a GIGANTIC .308 bullet in the top (of a case that you trimmed down, no less), fast burning powders are the only option.

The other interesting choice on the list is the CCI #400 primers. CCI makes a primer specifically for 5.56 ammunition called the CCI Small Rifle Military Primers #41, and the reason for the difference is that the primers are a little stiffer. The floating firing pin in the AR-15 rifle makes it possible to have a slam fire situation under the right conditions, and stiffer primers reduce that probability. That said, I’m on my third 1,000 count box of #400 primers and not so much as a single slam fire has occurred with either 5.56 or 300 BLK loads. Plus they’re cheaper, and so am I.

Let’s talk about powder weight.

The max load on a 300 Whisper load (from what I remember, don’t quote me) for 150 grain projectiles is somewhere around 18 grains of H110. At 18 grains everything starts to wear out quicker and the load becomes dangerous. There’s no real good load data for 300 BLK yet for the bullet weights I’m using, so since 300 Whisper is a lower pressure load one assumes it to be safe to use interchangeably. So, being the cautious guy I am, I started my load at 11 grains of H110. 11 grains is sufficient to cycle the action. Most of the time.

Yeah, that’s embarrassing. But with a silencer and the added back pressure it works damn near 100% of the time. Plus, the light charge makes the recoil as gentle as the morning breeze and keeps the wear and tear on the parts to a minimum. A fine “farting around on the range” load.

The only issue is with the lethality of these rounds for hunting. While the bullet will probably do the job at that relatively low velocity, I wanted something that was faster and with more energy for better expansion and a more humane kill. So I slowly worked up the scale until I hit 16.5 grains, which is high enough to give me a good velocity yet low enough to give me wiggle room for the cheap crappy powder thrower to screw up and still be below the max load. Not that I’ve ever had that problem, but I don’t like taking chances.

Despite my concern for the powder thrower being a POC, as it turns out these are some of the most consistent loads I’ve ever made. With an average velocity of 1,942 feet per second (within 100 FPS of factory loads), I get an IQR of 16 for these loads. For comparison, the most consistent factory load I’ve tested is somewhere around 20. Consistently zippy rounds are the key to accurate and humane kills, and these results are exactly what I like to see.

Which brings me to the reason I chose 150 grain bullets. The standard factory loading for supersonic 300 BLK is a 115 gr round, but there are a ton more options available at the 150 gr mark. Not only are there tons of cheap FMJ or SP rounds available from Hornaday and Remington, but there are also a wide variety of bullets specifically designed for hunting. Like the SST or GMX from Hornaday. Or the TSX / TTSX rounds from Barnes. And because they’re all the same weight, they can be used more or less interchangeably. Practice with the crappy cheap bullets, hunt with the good ones. After you’ve chronographed both and compared the ballistic profiles, that is.

The great thing about handloading your own ammo is that you can tailor your load to your application. Since this gun is primarily a hunting firearm, a quick yet consistent load is what I wanted. But if I wanted this as a competition gun, a lighter load would lead to faster follow-up shots while still making the power factor. In short, your mileage may vary. But for me, I like this load.

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  1. I keep toying with the idea of getting another upper for my AR, and the .300 looks like the clear winner. The utilitarian purpose of the round puts it right in the ball park for tasty mammals in my location, and that is quite the draw. Thanks for the video, Mr. Leghorn.

    • I was in the same situation and was looking for a good hog hunting option. I found a company that sells stainless steel barreled 300 Blackout uppers for less than $500. Way cheaper than buying a new .308. I reload using SST with 17gr W-296 and get extremely acurate shots at about 110 yards. Bought the upper from Star Armory

    • You don’t expand the neck. Most of the 5.56 neck Is cut off and then the body of the bullet is pressed in a die to form the .308 opening and neck of the .300blk, if I’m not mistaken.

      • The process is to remove the end portion of the 223/556 case and then form the new neck in a sizing die. It is a expensive process for the fun time shooter and sized, swedged, and polished brass can be purchased at

        • Forming the brass for 300 BLK doesn’t need to take any tooling that you wouldn’t already need to reload it. This video has you using a standard case trimmer (which you’d need anyway if you’re reloading rifle calibers) to trim down the case, and then the rest of the process is normal reloading–size/form/decap, prime, charge, seat bullet, optionally crimp.

          Now, using the case trimmer the way Nick does is pretty slow, and if you’re doing much volume you’ll probably want something faster. A $25 2″ cutoff saw from Harbor Freight will make quick work of cutting the brass to length. Combine it with some sort of fixture to locate the case at the right place (can be anywhere from a simple stop bolt on the vise of the saw, to a high-speed $50 device with a ball snap), and you can do 10 cases/minute or more with ease. If you go this route, you’ll add about $75 to whatever you would spend to reload the round anyway.

          tl;dr: At most, forming your own brass from used .223/5.56 will cost you about $75 more than loading pre-formed 300 BLK brass. If you’re trying to save money, it will cost you nothing extra.

        • I bought 500 once fired , reformed and primed 300 blackout cartridges on Gunbroker for $75 free shipping. I won’t have to worry about making brass for a while. Just an idea.

  2. I’ve been loading 110gr hornady v-max over 19gr of h110 and cci #400 primers. They’ve been pretty accurate for me. My only question is how it would hold up for deer or hogs. Being at a lower velocity I would think they would hold up but I’m unsure. I haven’t used them for hunting yet. Plus I need a chronograph before I continue load development. Any help would be great. Id like to use some of the 125gr ttsx but I haven’t been able to find any yet

  3. for 150 grain projectiles is somewhere around 18 grains of H110

    This is not too different from loads I’ve tried for my 357 Maximum revolver e.g. Lil’Gun 21 gr and 180 gr fmj target bullet. Other, slower, gunpowders often used for 357 Max are H4227 and Accurate 1680. The 357 Max brass is slightly longer than the 300 Blackout: 1.605 versus 1.386.

    • H110 has the reputation, for handgun loads anyway, of having a narrow loading range. Apparently one can’t reduce very far under the max load before incomplete ignition can occur.

  4. Cool article. I get the impression that you spend a lot of time reloading.

    It looks like your 150 grain load at 1940 FPS is putting out a little over 1250 foot pounds. What do you suppose the max effective range for that round would be on a deer sized animal?

    I’m also curious what your max energy “reasonable” load is. I was very stoked about 300 AAC until I started thinking about 150 yard plus shots vs. whitetail deer in my Dad’s swamp in WI. It seems to me that would be quite a stretch for a 5.56 or 300 BLK in the cold air where bullets lose speed much faster than SAAMI 59 degrees. Maybe I’m just in denial about how cool the 300 is…

    • 150 grain bullet at 1940 fps. That’s like a slow 30-30 load. I think my 30-30 launches the 150 grainer at about 2100-2200 fps.

      On deer sized game, the whitetails back home, I consider the 30-30 to have a max range of 150 yds. Realistically, in my experience, most hunting shots are under a 100 yds.

      • I’m looking at 15-250 ish yards where I will be hunting. I’ve been hunting there on and off for 15 years, and roughly 80% are below 100 yards. That being said, you might only get one opportunity a season, so I’m still thinking I need a little more power than the 300 BLK. My longest shot was a paced 320 yards (hey, it was before laser rangefinders!), and it was actually on my uncle’s farm.

        I’m probably going to take my .460 Revolver for short range, 6.8 SPC AR for medium, and .308 for the 5-350 yard shots. The 300 seems like it would be an excellent short range pig or deer gun, I just need a bit more leg. I still like the American AK 47 concept out of an AR, which is what I consider the 300 BLK to be.

        • In those conditions I would go with the .308. I was at one time a huge .30-06 fan but the .308 does it just as well until you get into really long range or heavy bullets.

          Being a vegetarian I haven’t hunted in years. But I still remember the time in the woods as some of the best. I do miss pheasant hunting the most. But I won’t kill for sport. Or trophy’s.

        • Hi,
          Go to the Wilson Tactical site or just search “7.62x40WT”. This a caliber that Wilson came up with just for the supersonic guys, it’s a 5mm stretched 300 blk and with the extra case cap it will throw a 125 gr. bullet at 2400 from an AR, add 100 fps for an Encore or Handi-Rifle.

        • Shooting a 16″ heavy AR with 110 Grn black tipped Factory bullets – my chrono is giving constant 2560fps at 3 feet from muzz. 150grn (30-30 flat nose berry) reloads run between 1800-1990fps depending on powder type and charge.

  5. Foghorn, articles like this would be a lot more accessible to the general reader if you would include footnotes defining your acronyms and specialized terms. Linking to Wikipedia articles or the equivalent would be fine, too.

    I’ve been learning about reloading by reading practical articles, but in this case, I got derailed and stopped at IQR. I challenge you to explain how someone unfamiliar with reloading terms would decode IQR by context clues in the text above.

  6. Does 300 Whisper have the same case volume as Blackout? If the case volume is larger with the Whisper then what’s a lower pressure load for Whisper could end up being a higher pressure load for Blackout. I assume they must be equivalent for you to make that statement.

    • The 300 BLK is a SAAMI approved version of the 300 whisper. They’re practically identical in form, but not pressure tolerances. Similar to 5.56 vs 223.

  7. I was watching TAC TV the other night and he (Larry Vickers) was schlepping for Daniel Defense (one of his sponsors) with one of their 556 and their new 300BLK and a AK for comparisons. I don’t know if he is not a fan of the new 300 or what, but in the comparison shoot off, it did worse than the other two in bullet drop and when shooting a cinder block. If DD is trying to get people on board to buy their new 300 AR, they did a bad job of selling their product!

    • I just saw this episode last night. The comparison was less then scientific and lacked some of the best detail regarding to 300 BLK cartridge. I really like TAC TV but this was just too off the cuff to be useful.

      Larry started out well explaining the weight of the 5.56 rounds tested but that went out the window with the 300 BLK (and AK). As we know from Foghorns GREAT posts, the load you’re running makes all the difference and IMHO that’s info that should be covered when talking 300 BLK.

      Nick… Maybe you can ramp Larry up a bit…. 🙂

  8. I just don’t see the 300 BLK as a good hunting caliber, sorry. There are two many other better options out there. If the attraction is to the AR platform, then an AR-10 type in both .308 and .243 would be my choice. With that setup I could hunt pretty much any game in North America.

    That said, a 10-inch barrel, suppressed AR using the subsonic 300 BLK would be the ultimate CQB rifle….


    • Cost of an ar-10 is just too much. I acquired a 300blk upper from Sota Arms at a gunshow for $400 and built a second lower later on for it at a cost of $200. That’s easily half of the cost of most ar-10s. Though I’d love an AR-10 just because.

      • IF, you’re going to hunt, and an AR-10 is to expensive, then I recommend a Remington 700. About as accurate as it gets out of the box. My 700 BDL in .308 never did bigger groups than 3/4-inch with quality ammo, and it did that all day long at 100 yards. You owe it to the game as well, most humane kill…


    • My neighbor’s daughter took her deer with a .22 Hornet. It’s all in shot placement, so pick the gun you’re most comfortable with. I like the knock-down and accuracy of my .308. Let’s not kid ourselves, the 300 AAC is just a damn fun bullet to play around with and adds a lot of adventure to the already fun platform of the AR rifle. We like building guns and bullets and all the toys that go along with. It wasn’t built for hunting four footed animals, but hey, if you’re comfortable with taking a deer with 300 Blackout, just know your data so you can have a clean kill.

    • On opening weekend this year, a co-worker took a 189lb(dressed) 16-point with a 300BO at 70yds. Critter made it 30yds before it was DRT. First year for rifle calibers in IN. He was shooting Winchester’s Deer XP round.

  9. I’ve found H110 decidedly suboptimal for 300blk.

    A5744 and A1680 are MUCH MUCH better powders for 300blk.

      • I load 17.5 grains of H110 for the 300 Blackout, CCI 400 primers OAL 2.060. Runs in my frankenar fine and burns pretty clean. I already use that powder for .45 colt so haven’t tried others. This 300 load runs 1.5″ at 100 yds with a $150 4x scope.

    • Never tried H110 for the 300 BLKout, also use the A5744 and A1680. Tried to use the A5744 for 223, but couldn’t get the load to cycle right. Some loads with 55gr didn’t eject the cartridge making me stop and make sure the barrel wasn’t plugged. The tolerance between min & max load is too close. I’m keeping the A5744 and A1680 for the BLKout with 150gr Hornady FMJBT.

  10. Nick , I don’t know if you’ll actually see this or not, but do you *actually* load your 150gr supersonics to 2.260″? I ask because I also load Hornady 150gr rounds (SP Interlocks #3031) and there’s no freakin’ way that the bullet will even chamber correctly for me if I load that long. I load them to 2.050 with 16.0gr H110 and I’m getting right at the same speeds (1950 fps). When I look at the bullet and seating depth that I’d get with loading to 2.260 there’s hardly any bullet in the case at that depth. Mind you, the SP Interlock isn’t long like the GMX or Interbond, but there’s no way you’d be using such and expensive round for plinking. So if you can, check the depth you’ve written in this article to see if it’s correct.

  11. Has anyone tries Win 231 as a powder for 300 BLK? I use it in my 9mm so I always have it around. I like keeping my shopping list simple with interchangeable ingredients. Anyway, I was wondering if 231 would be a good idea since the 300 blk case is so shallow hopefully I could get away with using this pistol powder.

  12. Nick,
    I found your post while I was searching for loading data for my 300 BLK. Thanks for posting your data. Your H110 load data for the 150g FMJ is almost identical to the load I worked up for my 300 BLK. My load is 16.2 grains of H110 with an OAL of 2.060″ which produced a 1.5″ three shot group at 100 yards. I think a better trigger might help tighten the group up a little. Do you have any data for 150g FMJ loads using 4227 powder?

  13. First I have a LAR-308 by DPMS and is very heavy compared to a normal 308 rifle or the AR-15.
    Second I can’t find any H110 so does anyone have any info for using Unique which is also a pistol powder and useable for the 44Mag in the 180-240 bullet weights.

  14. I have been experimenting with bullets for the 300 Blackout. I use Hogdon Lil Gun powder and have used two different Sierra bullets. Both are 125 grain bullets. The SPT Pro-Hunter (#2120) are short stocky soft lead tips. The Matchkings (#2121) are sleek hollow points. I loaded each with 17.5 grains of Lil Gun. Overall length comes in at 2.260 for the Matchkings and 2.075 for the SPT P-Hs. I have run 100 rounds of each through my 16″ SS barrel, and they have been flawless. I don’t have a way to measure the speed, so I can’t tell you anything about that, except that they should be 2100+ fps.

    I have just purchased some Nosler Customer Competition bullets in 168 grains and am looking for what weight of Lil Gun to put in. I can’t find any load data on the Nosler or Sierra sites for this heavy a bullet. The next step in the chart is up to the subsonic weights with only 9 grains as the max. I am sure that I can use more than that, but not sure how much more.

    Does anyone have any data for 168 grain bullets and Lil Gun powder? Am I going to have to use N120 instead of Lil Gun?

  15. I am a reader of this web site, but found this page by accident.
    I was looking for H110 recipes. Here’s the funny thing. I load 300 grain bullets with 49 gr of H110.

    What crazy high powered rifle is this? Its a handgun. .460 S&W.
    That gets things moving about 1800 fps.

  16. I’ve been using IMR 4427 (16.5 grn) behind hornady 150 grn SP interlocks with great success. Got some converted brass online to use for them. So far I’m happy with them, and my bullet choice is usually stocked at my local walmart, which is a huge plug. SST’s with the same weight and charge work well too, but they’re compressed.

  17. H110 is a bit fast for the blk with 150 gr bullets. With either A5744 or A1680 you can get mid to high 2000 fps with the 150s. I realise this is an old article and many bullets have since been developed to function at the slightly slower velocities of the blk. The barnes black tip 110 gr over a stout load of H110 or lilgun will get you to 200 yards easily. Same with the 100 grain cutting edge raptor (my current favorite). The 125 nosler ballistic tip has earned a good following. The 125 gr hornady SST over lilgun is an excellent performer as well. All of these bullets listed will get you to 200 yards with the black tip and the SST stretching that a bit further.

  18. I loaded some 300 aac bkackout using 150 grain hornaday fmj bullets the loaded ammo come out to be 2.07″ instead of the 2.26″ because these have a crimp groove. Will this still work?

  19. Just purchased a 7.62×39 AR upper from Palmetto State Arms. I have loaded 123 gr Hornady Soft Points, and 123 gr V-MAX over 26 grains of Widener’s SSP210 powder (which may be Nobel Sport Tubal 2000, similar to H4198), Winchester cases and CCI LR primers. Shoots 5 shot groups 1 1/2 to 2 inches using a 1x-8x scope. Russian FMJ ammo shoots 4-5 inches.
    Looks to gain a couple hundred fps over the 300 BLK and the Hornady bullets are designed for hunting. I need to get some Hornady 123 gr SST bullets and test for accuracy. They are designed for larger game.
    Perfect for the small Florida deer, hogs at short range, etc. Very close to 30-30 performance.
    My 16 inch carbine weighs 8.4 pounds with scope, less magazine and ammo. Recoil is not objectionable.

    Just acquired a CVA Scout in 300 BLK, 20 inch threaded barrel, $191 after call-in. Got some brass coming, new toy fun on the way!

  20. Question about muzzle energy on 300 BLK loads:

    I’ve been studying load data and noticed something that I don’t understand. In other cartridges that I’ve loaded, the muzzle energy is relatively the same regardless of projectile mass. Charges are lowered to compensate for heavier mass, (keeping the presures safe), but this is done proportionally and the m.e. stays relatively flat across the range of bullet weights.

    But when I look at 300 Blk, I see a huge variance in muzzle energy, with a noticable trend to much lower energy with heavier bullets. So charges/velocities are being lowered disproportionately with the heavier bullets.

    Example, At 110 Gn m.v. 2450, & m.e. is 1466 ft-lbs. But at 220 Gn m.v. 1263 & m.e. is 779 ft-lbs.

    Why is this?

  21. Old post, but I wanted to comment, because I’ve had to do much research on this myself.

    1800FPS is *generally* the minimum hunting bullets are designed to expand at. Thus, if you start at ~1950FPS as mentioned in the article, your range if you want to have any sort of bullet performance, is nil.

    This article is old enough that the Barnes 110gr projectile designed to open at lower velocities, and the Nosler ABLR’s (1300FPS minimum) probably weren’t out yet. As I’ve just gotten into .300BO myself, but have worked with a 16″ .308 for longer range hunting, I’ve spent a bunch of time researching this topic. The 110gr Barnes projectile, or the 168gr Nosler ABLR, are about the only bullets I am aware of that are going to give you any range, with an expectation of the bullet performing (on game), in .300BO.

  22. 125gr Sierra Pro-Hunter 2.060 OAL
    18.5gr Lil Gun Powder
    Lake City Brass
    CCI #41 primers

    19gr takes you to 2300fps

    Load zone = 18 – 19gr for hunting or 2200 – 2300 fps in a 16″ carbine.


  23. A great round with 125g hunting bullets, both fast and efficient. Think 44mag with better ballistics. I eat meat and kill for sport and trophies.

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