new 300 AAC BLK thread

[Grizz]

good article killing the entire 300 BLK idea:

http://www.alloutdoor.com/2014/05/22/300-aac-blackout/

I love articles like this. He glossed over the exact thing that persuaded me, the idea that I can have a high capacity pistol with as much ammo available as I am comfortable with, sitting beside me in the car, with performance on par with 45 ACP in a defensive load, and 300 meter range if necessary.

He totally overlooked the fact that it functions correctly with pistol gas because it is designed to function with pistol barrels. Duh. He faults the design because it doesn't function well in the AR with carbine gas. Duh. He sites the fact that it doesn't outperform the 762x39, unless you suppress it, or subsonic it, or whatever. And he doesn't note that the russian version of 762 is .311, eliminating the massive quantity of .308 bullets from comparison. He doesn't note that it is much more capable than the respected M1 carbine round. And he misses entirely that, while it is a boutique round for dotgovt types, it is a dream for handloaders, which both reduces costs to manageable, and opens up the performance envelope for custom loads, such as something that is appropriate for home defense.

He extolls the virtues of the 77gr 556, but not from a pistol barrel. Put an 8" 300 BLK up against an 8" 556 or an 8" AK and show us the results of that. It's a whole 'nother countryside out there when you do that. Don't expect your mule to pull the entire cart of borax by himself.

And he missed the fact that much of the enthusiasm over the round is focused on bolt action and single shot rifles that don't have gassing issues. Not ARs, but 300 Whispers all the same.

I am inexperienced with the round, just getting started shooting it, but from a pistol barrel with pistol gas it zings 'em out there and whacks the gongs with authority. That's all I know. I will eventually do my standardized water jug penetration tests.

For my niche needs I considered the AK pistol format, but didn't want to be stuck with its limitations, and wanted to try America's rifle in pistol format. Because I can. Plus I have to admit that I am a sucker for heavy-for-caliber slow moving bullets. When they come thirty or forty at a time, it's persuasive.

Grizz

[7.62 Precision]

A caliber I didn't think I had a use for.
http://thinkingoutsidethewire.com/2015/ ... a-use-for/

[7.62 Precision]

The article you posted is by Major Pandemic, who happens to be a friend of mine.

Like quite a number of my friends, he weighs energy heavily in comparing cartridge performance. I, on the other hand, feel that bullet energy is very much over-hyped when it comes to cartridge performance.

If we simply compare energy, he is right, the .45 ACP is just as good as a .300 BLK, and for the guys who worship at the alter of foot-pounds, that is the end of the story.

But when dealing with ballistics, we have to consider a lot more important things, like trajectory, sectional density, ballistic coefficient, etc. When considering a pig rifle that a small seven-year-old girl could easily handle, I considered a .45 ACP pistol mounted in a KPOS. I also considered 357 SIG. I really wanted that setup to work. But I did not consider them long - there was NO WAY that either pistol cartridge could give me the terminal performance on pigs that the .300 BLK can, and the .45 ACP would not come close to the trajectory, either.

Think of what a .45 ACP will do on game at 150 meters. Then consider a supersonic 300 BLK, or even a subsonic.

When sectional density comes into play, you will get penetration with the .300 BLK at every range, from the muzzle out, that the .45 ACP can't come close to touching. I have seen (and many others have seen) .45 ACP fail to penetrate car doors that 9mm zipped through, and the .300 BLK will penetrate far better than 9mm.

The Barnes Tac-X bullet will expand at very low velocities, so you have good terminal performance on game - if you have penetration and expansion, who cares about energy? It is largely irrelevant.

If I'm hunting caribou or moose with an AR, I want a 6.5 Grendel. If I am using an AR for long-range shooting, even if I was hunting from a tree-stand in the thick NE US woods, I would prefer a Grendel. In fact, for almost EVERY use I have for an AR, 5.56, 6.5 Grendel, or .50 Beowulf covers it far better than .300 BLK.

But if I want a short barreled AR that functions well, has good short-range terminal ballistics, and is not like holding a flash bang in front of my face when I pull the trigger, or if I want a dedicated suppressed weapon, .300 BLK shines.

Oh, and who cares if you have to use a pistol-length gas tube? It costs what? $15? And it's not like anyone really regularly changes out barrels - if you are building a .300 BLK upper, who cares how long the gas tube is?

[Grizz]

A caliber I didn't think I had a use for.
http://thinkingoutsidethewire.com/2015/ ... a-use-for/

Funny, a person could think I read this great article before I posted. I didn't, honest. But I appreciate that my thinking is working in this regard. For the moment, at least.

Looking forward to the hog hunt report. I've wanted to shoot one ever since my son got one that went over 300 on the ranch he lived on while in school. Oh, and his roommate shot up a bunch of them circling in his pickup and shooting out the window with his handgun. I forget the toll, but it was multiple hogs down that day. Dontcha just have to love that?

Is your daughter shooting the 300 now? How's she doing with it?

I'm thinking of cutting my barrel to 8.5 from 10.5. What are the best reasons not to?

[sore shoulder]

Well Grizz, I wrote my own article this morning in between chores and preparing my shop and truck to pull the tranny from my truck and rebuild it. Maybe this is the start of my own gun writing career.

I've been a big fan of the .300blk since I first read about it 3 years ago. Even talked my best friend into getting one. I still want one. It's the American 7.92 Kurtz. I love the cartridge.

But I can't disagree with most of what that writer had to say either, and have basically come to a lot of the same conclusions when I look at the actual ballistics people are getting. However, the only reason I take any exception at all to the 300BLK is the disingenuous hype. If people would stick to calling it what it really is and be honest about it's capabilities, I wouldn't have anything negative to say about it at all. I'm glad to see a widely available, easily converted with simply a barrel change .30 cartridge, and I hope it continues to become more popular.

But.

I've always been off put by the statements that it beats the 7.62x39. It's physically impossible for that cartridge to outperform the 7.62x39 in a apples to apples comparison. All the comparisons use a maximized 300BLK against a mass produced relatively low pressure soviet ball round, which is just laughable. I could handload a 7.62x39 to equal or surpass a 30-30 easily, it has the case capacity, I wouldn't need to modify the case at all. A 150gr bullet at 2400fps is easy peasy. Given the same gun/barrel length/bullet the 7.62x39 would walk all over the .300BLK. Any factory x39 load has more muzzle velocity and energy than 300BLK, and the downrange claims of the BLK beating the x39 don't wash out when you do the math, using the same BC bullet instead of a junky bimetal soviet bullet would disprove that easily. Almost all published loads for the x39 are kept below 40K psi and they still exceed the BLK. Contrary to popular belief, there is a very good selection of .311 bullets, a quick browse of Graf's, Midway etc. will quickly make this apparent. A high BC 200gr Lapua bullet could easily be loaded subsonic with a low flash powder. I've often wanted an H&R or bolt gun in x39 for just this reason, to play around with the cartridge and stretch it out. As far as ammuniton supply train, the 300 will never even begin to match half what you can get in x39 in our lifetimes, nor ever come close in price for plinking. We won't even go in to the near .308 Win capabilities from an Improved chamber that will still shoot soviet ball accurately. The big drawback to the x39 cartridge is magazine feeding issues and lug shearing issues on the non standard bolt face in an AR, that is the 300BLK advantage.

And similarly, all of the downrange comparisons I can find to 5.56 use the M855 ball. Start comparing the heavies and it loses it's advantage, and theres plenty of those available, Wideners has IMI 77gr milspec by the case way cheaper than any 300BLK. And again, we will just ignore the Improved chamber with near 22-250 performance that can shoot standard ammo accurately. There's no denying the short barreled suppressed advantage of the BLK with heavy bullets, but this is where the honesty about the 300BLK comes in. Compare it to optimized heavy bullets for .223/5.56 and it loses any long distance advantage. Factor in the ammo supply chain and it really loses.


As far as the AR wildcat rounds, it certainly has the lead, using all AR15 native components except the barrel, and a rapidly growing ammo support base, which is really the key to a cartridges success. Nothing would make me happier than to see this cartridge catch on with LE and mil and in turn create a huge supply chain. It is certainly the easiest .30 cartridge to convert to, and in a short barreled suppressed version it has a clear advantage over 5.56 and 9mm while still having some decent downrange performance at common combat engagement distances. As an all around short barreled CQB it is a stellar performer that can stand on it's own without making outlandish performance claims and I wish it nothing but success, and plan to contribute to that success in the near future with an upper of my own.

[7.62 Precision]

She will be shooting it for the first time tomorrow. It was cold before we left AK and we were racing to get ready for SHOT Show, so bu the time I had it together, we were flying out. Plenty of nice weather for shooting here in AZ, though.

I will get more photos and write a followup article as she trains with it, and then the main articles will come when we do the hunt. I will not be able to head right to TX from AZ this time, as all the guides are booked up for several months. It was not something I considered as I am nut used to being in areas where all the land is private. We will have to fly down from AK in a few months, when we can schedule something.

The 8" barrel is really handy in a vehicle. The photo in the jeep is for a vehicle defense article I am just finishing up, and I can say that in a tight vehicle like that jeep, the 8" .300 BLK pistol is much more maneuverable just getting the weapon out the window than a 14.5" AR carbine, and will fit in a much smaller space, making it easier to find a good, concealed way to carry it in the vehicle close at hand.

As far as cutting yours down, I don't see why not. You might just want to talk to someone who really knows the caliber and see if there are any considerations that we might not think of, like gas port size, etc.

The one I posted photos of started out as a CMMG pistol, and really is still a CMMG weapon, as everything in it is CMMG except that warthog lower. They seem to know their stuff when it comes to building these short .300 BLK pistols and rifles.

[firefuzz]

Although I sold it, after a very short break-in period, about 20rds, I never had any trouble shooting my 16" BO with a carbine length gas system with subsonic ammo. The buddy that bought it shoot subs in it all the time and he doesn't even own a can.

I think the 300 Blackout is a fine cartridge, but it wouldn't be my first/only choice as a cartridge in a M4/M16 combat rifle. OF THE CARTRIDGES I HAVE EXPERIENCE WITH that would be the 6.5 Grendel. The only reason the .223/5.56 is my go to cartridge now is time and money....over time I've spent a great deal of money building my arsenal and stock pile. I don't have either to start over with a different cartridge. I am fixing to build another BO in a pistol version tho.

Rob

[sore shoulder]

If we simply compare energy, he is right, the .45 ACP is just as good as a .300 BLK

The only time the .45 ACP compares to the BLK is when the BLK is using subsonic rounds, however, you get +P .45 ACP performance in a subsonic round from the BLK, with a nearly 3x higher BC that will carry that performance a lot further, all from a common 30 round mag. Once you go supersonic you have 2.5x the muzzle energy which again is going to carry a lot further and a lot flatter.

[carbluesnake]

7.62 is right about the foot pounds of energy(FPE) thing. FPE has nothing to do with stopping power, killing power, or penetration. FPE is all about velocity, which is not a bad thing in itself, but FPE has its limitations in the real world. If you read about african hunters or read any of Elmer Keith's stuff, they will tell you that if you want to stop dangerous game, bullet weight and diameter is what you ought to look for, not velocity. 45 auto produces pathetic FPE, but 100 years of real life experience will tell you that it performs way better than its FPE figure. Look at the 38/55 or the 45/70 FPE figures. They are pretty sad, but no one who has any sense will criticize their ability to do the job.

[7.62 Precision]

. . . you get +P .45 ACP performance in a subsonic round from the BLK, with a nearly 3x higher BC that will carry that performance a lot further . . .

. . . and a MUCH better SD, which equals a penetration potential far beyond what .45 ACP is capable of.

[Grizz]

. . . you get +P .45 ACP performance in a subsonic round from the BLK, with a nearly 3x higher BC that will carry that performance a lot further . . .

. . . and a MUCH better SD, which equals a penetration potential far beyond what .45 ACP is capable of.

which, it turns out, is actually a problem for certain aspects of self defense. for the scant amount of powder used, it is very efficient with the pointy little things. room for development.

[Grizz]

7.62 is right about the foot pounds of energy(FPE) thing. FPE has nothing to do with stopping power, killing power, or penetration

it is momentum that produces all of those things. if I understand 556, the tumbling frangible bullet uses the momentum to self destruct. it is momentum that gets the 220 subsonic BLK round thru 30 some inches of ballistic gel, or 3 bad guys. or a car door and two bad guys.

I'm wondering if a subsonic 100 grain bullet would cycle the pistol.

[sore shoulder]

. . . you get +P .45 ACP performance in a subsonic round from the BLK, with a nearly 3x higher BC that will carry that performance a lot further . . .

. . . and a MUCH better SD, which equals a penetration potential far beyond what .45 ACP is capable of.

which, it turns out, is actually a problem for certain aspects of self defense. for the scant amount of powder used, it is very efficient with the pointy little things. room for development.

I think it's a matter of proper bullet at that point, something designed to open/fragment rapidly at lower velocities.

[sore shoulder]

Hey Grizz, hows a 160gr cast at 2100fps tickle you?
http://www.300blktalk.com/forum/viewtop ... 41&t=82836

[7.62 Precision]

Barnes 110 gr. TAC-TX bullet.

Barnes claims a muzzle velocity of 2350 fps and over 1360 FPS at 400 meters. I assume that is based on a 16" barrel, as I have seen real world reports of around 2200 fps give or take from various hand loads out of an 8" barrel.

This is interesting because Barns says the bullets will reliably expand fully (.50) at velocities as low as 1300 fps, so that means if you have a MV of 2350 fps, you will get expansion out to 400 meters.

Users have reported pretty devastating partial expansion at lower velocities. I would still expect deep penetration from this bullet.

I saw a bullet in the making at SHOT that is VERY interesting. I will post the info for you guys when I can. As this cartridge matures, it is natural that we will see more companies design bullets for the cartridge instead of just using bullets designed for higher velocities.

[sore shoulder]

I have been trying to upload this photo using several different methods and keep getting "cannot determine dimensions" or "can't be more than ___ pixels". No matter how I try to work around it.

Anyway here's the image link for a very cool chart comparing barrel length and energy betwen M193 and a Barnes 110 300BLK. Not sure how accurate it is but it at least puts things into perspective for muzzle energies.

http://img.photobucket.com/albums/v726/ ... 3682_o.jpg

[sore shoulder]

Barnes 110 gr. TAC-TX bullet.

Barnes claims a muzzle velocity of 2350 fps and over 1360 FPS at 400 meters. I assume that is based on a 16" barrel, as I have seen real world reports of around 2200 fps give or take from various hand loads out of an 8" barrel.

This is interesting because Barns says the bullets will reliably expand fully (.50) at velocities as low as 1300 fps, so that means if you have a MV of 2350 fps, you will get expansion out to 400 meters.

.

A quick calc on muzzle energy @2200fps gives 1181fps. Even at 2100 it has over 1000fpe. That's 44mag performance from an 8" barrel, and even with a 20 round magazine to lighten it up and keep it compact that's at the least impressive.

[Grizz]

Hey Grizz, hows a 160gr cast at 2100fps tickle you?
http://www.300blktalk.com/forum/viewtop ... 41&t=82836

isn't that right at 30-30 performance ? isn't that more than X39?

[Grizz]

Barnes 110 gr. TAC-TX bullet.

Barnes claims a muzzle velocity of 2350 fps and over 1360 FPS at 400 meters. I assume that is based on a 16" barrel, as I have seen real world reports of around 2200 fps give or take from various hand loads out of an 8" barrel.

This is interesting because Barns says the bullets will reliably expand fully (.50) at velocities as low as 1300 fps, so that means if you have a MV of 2350 fps, you will get expansion out to 400 meters.

Users have reported pretty devastating partial expansion at lower velocities. I would still expect deep penetration from this bullet.

I saw a bullet in the making at SHOT that is VERY interesting. I will post the info for you guys when I can. As this cartridge matures, it is natural that we will see more companies design bullets for the cartridge instead of just using bullets designed for higher velocities.

I have a box of those, but I haven't shot them. Seems like the pd and 'yote shooters would be all over this. I wonder how it does on hogs.

I wonder if handloading this to 1300 from 8" would keep the overpenetration down?

I can't remember my 7mm load, but I quit shooting deer with 7mm because the bullets would stay inside. funny how times change things.

[sore shoulder]

Hey Grizz, hows a 160gr cast at 2100fps tickle you?
http://www.300blktalk.com/forum/viewtop ... 41&t=82836

isn't that right at 30-30 performance ? isn't that more than X39?

Yes, jacketed 30-30. Very low end. It's no trick to push a 170gr 2300 in 30-30.


You can push a jacketed 155 gr 2400 fps in x39.

[AJMD429]

Hey Grizz, hows a 160gr cast at 2100fps tickle you?
http://www.300blktalk.com/forum/viewtop ... 41&t=82836

That is plenty for deer!