.300 blk out question

[entropy]

I'll tell you the only reason I haven't built one yet-It'd be another caliber to stock and reload. I could also mention that I have guns in .30-30 and 7.62x39, so I don't need it for the 'brush gun' niche, I don't hunt hogs (which it is a great caliber for,but not many feral hogs in WI) I don't need it for it's designed application, and there are many other guns that I'd like to get first. Maybe if I find an upper for dirt cheap, I could pick up a couple boxes of ammo and tuck it away, but I don't see one in my immediate future.

Now if I lived in TX....I'd have a rig like Double Naught Spy's hog gun.

 

[someguy2800]

Lil'Gun is indeed one of the fastest powders you can use in the 300 BLK. Probably the fastest powder. But at what cost? Lil'Gun burns hot, due I am told to it's nitroglycerin content.

Lil'Gun gets me almost 2000 fps out of my 16" barrelled 300 blackouts with the 150 grain pulls I like to use for plinking. I also like that the charge weight for the subsonic is 1/2 of what my supersonic loads are. Charge the case once for 208's and twice for 150's.

But there have been problems, not with my MSR's that I can see, but with my 410 loads. Hulls will not last when using Lil'Gun. And while I have not used Lil'Gun in any of my revolvers, reports are many that there have been damage to the forcing cones when using this powder.

Lil'Gun is still my go to powder for my 450 Bushmaster, but I have pretty much quit loading it in anything else. I have about 2 pounds of Lil'Gun left, when it's gone I will be replacing it with H110/W296. The performance is comparible in the 450 Bushmaster, but the velocity loss in the 300 BLK is close to 200 fps!

In my gun H110 netted 2400 fps at book max, and lil gun was just over 2500. Problem was that when I tested both loads in the cold on a -30 deg F day, the lil gun load was wildly over pressure. The first shot blew the primer, the 2nd shot blew the primer and dramatically expanded the case head. I pulled the rest of my lil gun loads after that and threw the rest of the lil gun I have away. No more for me thanks!

 

[someguy2800]

One other thing I will note, I built my blackout with the intention of getting a suppressor for it, which I’m still waiting for. In the mean time I put a krink brake on it to quiet it down some and loaded up some super and subsonic loads. I expected it to be fairly quiet with subsonics and the krink brake of a 16” barrel but it was not. I couldn’t really tell the difference between subs and supers. I rebuilt the upper as a 7.62x39 but I kept the barrel so when my suppressor comes through I will put together another upper to use it on.

 

[JeeperCreeper]

300 BLK is the gateway drug to multi-caliber AR builds.

Requires little part difference and virtually no tuning.

Plus if it's a pistol/sbr format with good loads, it can be quite effective.

 

[CANNONMAN]

OK. Thanks. My buddy is not a member here but I'll get him over here to read your responses. If his issues are other than the info given here I'll bring them up. I have three .300 blc outs and just love to play with them. I'm sure there's a lot of response to this but, one of my pet HD is a suppressed .300 SBR

 

[Sushigaijin]

I like it for home defense. I dont know any other chambering - and anyone may correct me if I'm wrong - that moves a 110g vmax/barnes blacktip at over 2100fps out of 7.5" barrel. 30 rounds on tap. Tiny gun. I have a 16" for hogs, the recoil is very light so I have lots of follow up power. 110vmax gets closer to 2400fps out of the carbine. 125sst books over 2200.

 

[TIMC]

300 BLK is the gateway drug to multi-caliber AR builds.

Requires little part difference and virtually no tuning.

Plus if it's a pistol/sbr format with good loads, it can be quite effective.

This is exactly how I ended up with 9 AR’s!

 

[Varminterror]

I dont know any other chambering - and anyone may correct me if I'm wrong - that moves a 110g vmax/barnes blacktip at over 2100fps out of 7.5" barrel.

Pretty certain both the Grendel and 6.8SPC clear 2100fps behind a 110 in a 7.5” without breaking a sweat. I know my SPC can. My shortest Grendel has been 10.5”, and it cleared 2300-2350fps without swipes.

 

[TIMC]

One other thing I will note, I built my blackout with the intention of getting a suppressor for it, which I’m still waiting for. In the mean time I put a krink brake on it to quiet it down some and loaded up some super and subsonic loads. I expected it to be fairly quiet with subsonics and the krink brake of a 16” barrel but it was not. I couldn’t really tell the difference between subs and supers. I rebuilt the upper as a 7.62x39 but I kept the barrel so when my suppressor comes through I will put together another upper to use it on.

The B/O is nice with a suppressor I liked 300 B/O so much I built 3 guns.
this is my SBR.


This is the 16” B/O.

The Ruger American Ranch B/O

 

[someguy2800]

The B/O is nice with a suppressor I liked 300 B/O so much I built 3 guns.
this is my SBR.
View attachment 795521

This is the 16” B/O.
View attachment 795522
The Ruger American Ranch B/O
View attachment 795523

That ruger in the Boyd’s stock looks awsome

 

[Sushigaijin]

Pretty certain both the Grendel and 6.8SPC clear 2100fps behind a 110 in a 7.5” without breaking a sweat. I know my SPC can. My shortest Grendel has been 10.5”, and it cleared 2300-2350fps without swipes.

I did not know this, I will look into it - my next build will be a rifle caliber (not 5.56 or 300aac) with some gettyup, and I've been considering grendel for it. I have also considered 6.8, but I have read mostly mixed reviews. I guess I've never seen a grendel pistol - not that I've looked very hard.

300blackout does have the advantage of being VERY mild to shoot - even the supers are relatively quiet and soft compared with 7.62x39 or 30-30. It's certainly not a macho round, but part of that is it's attractiveness. Plus it's easy to reload if you already have guns in 5.56 or 308. I've been buying cheap Remington UMC ammo, shooting it because it is pretty accurate and hot enough, and harvesting the brass. With Cabela's periodic 20% off Hornady reloading component sales, I have been loading 110 vmax and 125 SST for about 28 cents, including primer and charge, once I average in the price of the factory ammo, based on 5 reloads.. That's not bad for centerfire PRACTICE ammo, let alone high quality hunting ammo. Those are all pretty good reasons to shoot 300 blackout, even if you cannot get a suppressor.

 

[TIMC]

That ruger in the Boyd’s stock looks awsome

Thank you.

 

[CraigC]

Do it!

 

[MTMilitiaman]

The haters always seem to have unrealistic expectations. When you understand what the cartridge is, what it does well, and you have more realistic expectations of its performance, it makes more sense.

If you want the most range and performance you can get from the AR-15, the .300 BO is not it. Look to the 6.5 Grendel or other wildcats. On the other end of the spectrum, if you want as much performance as you can get from a short rifle at close range, the 6.8 SPC and the .300 BO are really good options with the .300 being generally cheaper and easier to set up. If you plan on running a suppressor, the BO has capabilities that make it shine, and if you want a AR pistol with ballistics that don't suck, the .300 BO is kind of the only game in town.

 

[Varminterror]

if you want a AR pistol with ballistics that don't suck, the .300 BO is kind of the only game in town.

Lots of other options. The 6.5 and 6.8 will push the same bullet weight faster than the blackout, with better ballistic coefficients and sectional densities. Even the 6x45 will push the 100grn bullets to nearly the same speed as the Blackout, and with better ballistic coefficients. 6mmAR, FatRat, Turbo, 7 Raptor, valkyrie, 30 AR, 30 American, even x39, and likely around a dozen others will deliver better ballistics out of equal barrel lengths to a Blackout.

The .300Blackout is cheap and easy to adopt, but it’s performance is very largely exaggerated against the rest of the field.

 

[CoalTrain49]

Some people don’t know what they’re talking about. Others repeat what they hear and the little they know.

300 Blackout seems like a very interesting option. It’s on my list, but I reload and I like the thought of recycling some damaged brass that I have into something useful.

I also like the thought primalmu has of the 6.5 Grendel.

But that’s me. Some like my brother don’t like having to too many calibers.

So each his/her own.

Personally I think you need to find out what your friend wants and needs. Then make a recommendation based on that rather than speculation.

I've been looking around for a 30 cal. cartridge that doesn't use a lot of powder and would make a good 100 yard plinker/range gun. I've never really thought about the 300 BLK until I saw a case at the range. After I examined it I saw it was 300 BLK. Well that could be just what I'm looking for. I have several thousand 110 grain FMJ bullets that I will never use in my 30 carbine M1. I only shoot it about once a year. I looked in my Hornady manual and it can be loaded with these bullets and about 15 grains of 2400 for around 2000 fps. In essence, it's a modern 30 carbine, but a lot more versatile being able to use heavier bullets. I also have several thousand pieces of 223/5.56 brass I could cut down and resize.

Now all I have to do is find a bolt rifle that is chambered for 30 BLK. This might be fun.

 

[LoonWulf]

Now all I have to do is find a bolt rifle that is chambered for 30 BLK

Ruger American Ranch. I really liked mine, the blackout just didnt work for what i wanted it for. Otherwise super cool combo.....

Now i want a RAR in x39...

 

[adcoch1]

Ruger American Ranch. I really liked mine, the blackout just didnt work for what i wanted it for. Otherwise super cool combo.....

Now i want a RAR in x39...

This^^^^^

 

[Sushigaijin]

The .300Blackout is cheap and easy to adopt, but it’s performance is very largely exaggerated against the rest of the field.

It's also very mild to shoot, with minimal report and micro recoil - since it has good powder burn in short barrels, it's not blowing a ton of unburnt powder out of the front too. I think of the 300aac as a pistol cartridge that can be used in carbines. It's almost a rifle caliber, and almost a pistol caliber. If you need a bridge gun, that is where it is useful. I'd take an AR pistol or SBR in 300aac over 5.56 any day of the week. Just the difference in concussion alone makes it worth it, plus the 300 has superior terminal ballistics out of those little barrels. It's all about managing your expectations for this round - it will do what it can do, and not more.

 

[rabid wombat]

In 300 BO, an AR, a bolt action, and a barrel for a T/C pistol....go for versatility.

 

[MTMilitiaman]

Lots of other options. The 6.5 and 6.8 will push the same bullet weight faster than the blackout, with better ballistic coefficients and sectional densities. Even the 6x45 will push the 100grn bullets to nearly the same speed as the Blackout, and with better ballistic coefficients. 6mmAR, FatRat, Turbo, 7 Raptor, valkyrie, 30 AR, 30 American, even x39, and likely around a dozen others will deliver better ballistics out of equal barrel lengths to a Blackout.

The .300Blackout is cheap and easy to adopt, but it’s performance is very largely exaggerated against the rest of the field.

Out of a short barrel the .300 BO will smoke the x39. I've seen it. The .300 BO was designed around faster burning powders and short barrels. It uses the same magazines and bolt as the 5.56. So maybe I should say that the .300 BO is the only game in town that doesn't require obscure ammo, parts, and magazines.

 

[greg_r]

I will agree that the 300 BLK is the best option for an AR pistol. I look at the BLK as something near the 357 Maximum. Bellm T/C's has the 300 Whisp-R which is the 300 Whisper formed from 357 Maximum brass. I do the same thing with my AAC Handi Rifle, except I generally use 357 Magnum brass which works well, just leaves a short neck.


I have tried, and succeeded, in getting more power from the AR platform. I do like my 6.5 Grendel and my 450 Bushmaster. I just keep waiting for the bolts to break. I have seen a few broken 7.62x59 bolts. My 6.5 Grendel II bolt is still good after a bit of shooting though. I'm thinking the deeper bolt face makes a difference. The 450 Bushmaster is new to me, only a few hundred rounds down the tube. AR bolts are a wear item anyways, learned that as an armorer in the Corps. It's not a matter of will an AR bolt break, but when. I do keep spare bolts, and when Ruger released the American Predator in 6.5 Grendel I grabbed the first one I could, along with the American Ranch in 450 Bushmaster. I have spares!

I favor AR's that use standard STANAG spec parts and try to stick with cartridges that have the standard 223 rim size. Hence my other thread about finding a cartridge that will give me better performance than the 300 BLK and close to the 6.5 Grendel in a reasionably sized hunting rifle. I made a choice that I think will be better, but only by a small margin. I was hoping for 2600 fps from a 120 grain 7mm bullet, but looks like that ain't going to happen. The inventer of the cartridge I choose responded to an e-mail and stated that they are seeing 2550 fps with 1680 pushing a 110 grain bullet out of a 18" barrel.

The point I am making is I just don't think you will do much better than the 277 WLV, 300 BLK, 25-45 Sharps out of a MSR using STANAG compatible cartridges. I wish I could of gotten the accuracy out of the 25-45 Sharps.

 

[ColoradoMinuteMan]

I've got a friend who sent a bunch of AR 15 parts off to a custom shop. They went out of business and it took a potential law suit from a collection of similar customers to get their parts back. Now saddened he tells me he doesn't know what to do. I told him that since he has four other AR 15's why not put together a .300 blk out? This is when he tells me that others have told him they wouldn't do that and to go ahead and have me put together another AR 15 as he was going to have the shop do. I told him I had no real reason why anyone would tell him that and that I would post his issue with all the like of you who may read and reply to the question. So, why would you not want a .300 blk out? Especially if you already have four AR 15's, three are for the "having" only and are rarely shot.

What we the purpose of the customization he was looking to get done? Was it just to have something new and interesting or did it have a specific requirement in mind? If he was paying a custom shop to build something I’d expect he had a purpose in mind. The purpose should drive the cartridge type.

 

[CraigC]

There are cartridges that do subsonic better and there are cartridges that do supersonic better but there are plain few that do so well at BOTH. Especially now that we have ~200gr bullets that expand at subsonic speeds.

 

[hq]

Out of a short barrel the .300 BO will smoke the x39.

For subsonic loads and short barrels they're pretty much equals with no discernible difference one way or the other. The larger case capacity of x39 just gives an advantage at the upper end of V0/E0 echelon, all the way to compression loads in the larger case. The heavily tapered x39 isn't ideal for the straight magwell of AR and that's where the BO has an advantage. It's a very specific cartridge for a very specific purpose and the go-to round for factory subsonic ammo because of sheer availability. Handloads can quite literally duplicate the performance and characteristics easily in either.

In short, in a standard lower AR platform the BO is great.