Range Report Considering a 300 Blackout

surprise

Sergeant
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Minuteman
Mar 23, 2010
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I have shot 556 and 308 for years and like them both well enough. After talking with a shooting buddy he keeps raving about the 300 BLK. I don't know much about it other than it seems to be the more popular new kid on the block for the AR platform. I have heard in passing about some "operators" using it, especially with something like the Sig Rattler.

Really trying to decide if its a caliber that I want to get into or not. Something like the Sig Rattler does seem super appealing for its size and ability to shoot with out any sort of buffer tube..... I would like to hear your thoughts on shooting 300blk and what the ballistics are like compared to 556. Personal experiences are welcomed. Would probably be looking to use it as a home defense rifle and of course for running and gunning fun stuff....

Thanks
 
It's a lower velocity round, so expect that from the start. It's a nice setup for shooting heavier bullets than 5.56 with similar recoil and less blast, and is generally a very mild shooting experience. Just don't expect it to be a magnum or even a 308; it's an intermediate cartridge a lot like the 7.62x39. It's easy to suppress and is very efficient in shorter (like 9"-10") barrels, and full power supersonic loads only use around 15-20gr of powder, depending on the load. Subsonic loads can use half that, or less.
 
MORE ENERGY
More energy than 30-30 Win., 300 Blackout and 223 Remington
LESS RECOIL
Less recoil than 450 Bushmaster

How did I miss the 350 Legend... Oh, I know prefer my 260?
Yea, once had Z car too...
 
It's a lower velocity round, so expect that from the start. It's a nice setup for shooting heavier bullets than 5.56 with similar recoil and less blast, and is generally a very mild shooting experience. Just don't expect it to be a magnum or even a 308; it's an intermediate cartridge a lot like the 7.62x39. It's easy to suppress and is very efficient in shorter (like 9"-10") barrels, and full power supersonic loads only use around 15-20gr of powder, depending on the load. Subsonic loads can use half that, or less.

One of the down sides I see already is the manufacureded ammo is damn near the price of 308! Wasn't expecting it to be 556 pricing but not expecting 70 cents a round either....
 
One of the down sides I see already is the manufacureded ammo is damn near the price of 308! Wasn't expecting it to be 556 pricing but not expecting 70 cents a round either....

Yes, that's definitely a factor if you buy factory ammo. And BTW, the Remington subsonics are junk, don't waste your money.
Personally I load my own and don't pay much attention to factory ammo prices. 300 Blk is as cheap or cheaper for me to load than 5.56, mainly because it uses less powder. That's not my motivation for shooting it, but it's a pretty big difference from comparing factory ammo in either one.
 
Yes, that's definitely a factor if you buy factory ammo. And BTW, the Remington subsonics are junk, don't waste your money.
Personally I load my own and don't pay much attention to factory ammo prices. 300 Blk is as cheap or cheaper for me to load than 5.56, mainly because it uses less powder. That's not my motivation for shooting it, but it's a pretty big difference from comparing factory ammo in either one.
So sounds like you are a fan then? I think it makes sense with the size bullet you can use compared to a 556. Just really having some heartburn about doing another caliber......
 
I have 2 rifles in 300 blackout or 300 Whisper and my favourite load is 11.6 grains of AA1680 under a 240 grain Sierra MatchKing.
Two years ago I used it to shoot a nice 3X3 blacktail.
Never tried either of them with anything but subsonic ammo.
 
Have 16 inch bolt gun and 10.5 sbr.
Would not trade for either.

So much fun to shoot subs suppressed.
It's a great trainer for a new shooter.
It's a good short range management tool if you like peace and quiet.

The greatest expense is the 220g bullets I use @.36 cents there are cheaper choices for plinking.

I have not found one single acceptable factory round.

12.1 cfe blk 220g fbrn @1060fps pet load.
Just do it.
 
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I just built one. It's definitely not a long range round. The big selling point to me is the efficiency out of short barrels. 8.5" barrel with Q thunder chicken is shorter than 16" barrel and muzzle device. Even with that short of a barrel you still have good enough ballistics and more close range energy.

7039047
 
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16" bolt and 10.5 AR. The AR doesn't see much use these days. With 6.5 gr of VV N32C and 150 FMJ, it's stupid quiet and fairly accurate
out to 275 yds. ( .8" @ 100 yd). I can also replicate the trajectory of my 6BR at 4:1 ( 250 yds= 1000 yds) with a 75 yd zero.
Waaay too much fun ?
 
So sounds like you are a fan then? I think it makes sense with the size bullet you can use compared to a 556. Just really having some heartburn about doing another caliber......

I don't consider myself a fan of any particular round, like some guys do, but yeah I like the 300 Blk for what it is; it's a good little round that fills a certain role very well.

I will say the subs are a fun novelty, but most of what I shoot in mine is 110-125gr supersonic loads.
 
I don't consider myself a fan of any particular round, like some guys do, but yeah I like the 300 Blk for what it is; it's a good little round that fills a certain role very well.

I will say the subs are a fun novelty, but most of what I shoot in mine is 110-125gr supersonic loads.

What do you think your effective range is?
 
+2

It's the bastard child of 223 and 308, if you already load those you have what you need. Take a 223 case, chop the top off and shove a 30 call bullet in it and you have a 300blk

7" pistol shooting 220gr 30cal subsonic
Or
18" rifle shooting 110gr 30cal at 2400fps

Broad spectrum of uses and fun.
 
I haven't stretched it out very far, but at least 300 yards on a silhouette target from my 9" pistol. That's talking about supersonics here of course; it's basically 7.62x39 ballistics but with more streamlined bullets, and some like the Barnes "black tip" 110gr will open up at pretty low velocity, around 1300 fps IIRC. With subsonics of course it's the rainbow trajectory that limits the range, but they can be fun to plink with at distance.

My short 300 is more limited by the optic choice than the cartridge itself; it usually just wears irons and a red dot. I'll occasionally mount a 3-9x on it for load development or for a kid to hunt with; even then it's really not a long distance cartridge but does well as an intermediate round. A 16" barrel is a little easier to shoot at distance, and will cover any distance a 30/30 lever action can (mainly because of higher b.c. bullets), but it doesn't run a whole lot faster than a 10"-11" barrel.

Speaking of barrel lengths - mine started as an 11", and after a few years I cut it back to 9". That lost about 100 fps with 125gr supersonic loads. I wouldn't want any shorter than 9" for what I use the gun for, and would consider staying with 10.5" if I did it again. The 9" gun is a nice size package though (especially with the LAW folder) and still very effective. It worked well for my son's first deer last fall with a 125gr NBT; one shot and done.
 
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Another one with a 16" bolt and 10" SBR here. Agree with a lot of what has been said above for cost to reload, fun to shoot, etc. It is a very versatile round that can shoot pretty much any 30 cal bullet.

16" bolt - really just fun to shoot. Shoot both supers and subs suppressed. Use it for hunting, but probably wouldn't really hunt with it over 200 yards. Have had it out on steel at 600 (supersonic). I'll shoot subs to 300. No complaints.

10" AR - Have shot supers and subs out to 300+ yards. Like said above, optics and eyesight are more of limit than the round I think. It is pretty much a CQB type rifle now that wears the IR and white lights and shoots only suppressed. Fun and quiet.

Prices have been coming down for factory stuff.

Would recommend a pistol length system vs carbine length for AR as it will get you most reliable cycling and open up powders you can use. Ultimately, buy it for what it is - a short to mid range round. Don't try and use a wrench to hammer in a screw and you'll be happy. It is hard to find long ranges around here, so for me, 300blk works perfectly as it allows me to practice to 500+ easily for cheap. Add subsonic into the mix and it is quiet, cheap, and a bit more difficult due to drops.
 
My 10.5" 300blk is one of my favorite guns. I built mine for accuracy with supers from 100yds and in. I went through 2 barrels that shot like buck shot. 3rd barrel I grabbed was a Rainier Ultramatch and it's a tack driver. I have both their Ultramatch first gen and their new Mod 2. Both are extremely accurate.

I shoot 125 TMK with 18.6gr of H110 at 2150. I have no problems hitting steel with 100% consistency out to 500M with a 1.5-5x optic.

I didnt build it to shoot at distance but after seeing how accurate it was I decided to walk it out on steel to see how far I could go before it was making consistent hits. Went 10/10 on steel at 200M, 300M, 400M and 500M.








 
I've been watching my best Buddy shooting partner going through the exercise of developing his own homebuilt 300BO AR pistol. He had fallen in love with the chambering before he had even built it, and he still loves it, probably even more than when he started. But the path has not been without some lamentations.

The main concerns center around brass. Some of his earlier handloading efforts, especially with his own formed brass, proved difficult to get good shoulders and necks. He's reusing commercial 300BO brass now, and the cases are good, but there's still an issue; primer pockets. He can only get around 3 loadings before they get too big, and he's being conservative with the loads since he first noticed the issue.

Nominally, the overall pressure should be mild and tolerable, but I suspect there's an unavoidable issue happening when the bullets obturate into the rifling. I think there's so much bearing surface engaging so very forcefully that there's a monster pressure spike happening instantaneously, and that this is what's blowing out those primer pockets. But I also think my Buddy is quite prepared to live with the reduced primer pocket life, so maybe I'm barking up an empty tree.

It's just a notion with nothing to provide confirmation. But I think it's worth consideration. I keep being tempted by the 300BO; but with my Ruger PC Carbine, I also wonder what would be the point?.

Greg
 
Sounds like your buddy needs to figure out what he's doing wrong, because thousands of other 300 Blk shooters and handloaders, myself included, don't have the problems you described. I make my 300 Blk from LC 5.56 brass. Shoulders are fully formed on the first firing (and are almost fully formed even before firing), and the case handles just as much pressure as it did in 5.56 form with no issues whatsoever. Typically 300 Blk loads are a little milder than mil 5.56 ammo anyway.

Maybe he's using FC 223 brass? That stuff is known to be soft in some batches, and a lot of guys won't use it because of that.
Either that, or he's got headspace issues from poor sizing methods.

Don't know what your buddy is doing to "develop" his own 300 Blk pistol, but the 300 in a pistol AR has been figured out and well understood for quite a while now. Any problems he's having are because he's deviating from the configurations that are known to work reliably. It's not like this is a new thing that nobody is familiar with yet.
 
Possibly something in how he removes the crimp or cleans the pocket?
I have many mixed head stamps and formed brass none has had a primer problem.

I shoot 220g subs with cfe blk at max 12.1
About 0.0025 neck tension and a light crimp.
Maybe a powder burn rate problem?
 
I shoot a lot of hogs at night with mine. Mostly subs but if I can’t get close enough I carry a mag of supers with Barnes blacktip and 2-300 yards is no problem even with a red dot. For subs I run the Nosler custom competition overrun or seconds from shooters pro shop. If you wait you can find then for around .15cents. They just pencil through but you put a couple in them they will drop. Follow up shots are easy with a suppressor. Run an adjustable gb and recoil is almost non existent on subs
 
I have 2 ar's I built chambered in 300blk, one I deer hunt with and after seeing what it does to the insides of a deer I decided I needed one as a truck gun. Also the fact that I'm hopefully just a couple months from having my form 4 approved was a motivating factor in messing with 300blk.
 
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The only reason I got into 300 blk was because of my suppressor. If you aren’t suppressing it, I don’t quite get the perks of sub sonic 300 blk. If you are shooting supersonic, it’s much like the 7.62x39. I like it because it’s slower and I can shoot my steel at 100 yds and not worry about pitting like 556. I was very briefly thinking about getting a 300 blk bolt gun to shoot suppressed, then I loaded trailboss in my 308 and WOW it was stupid quiet and as accurate as I needed it to be.
 
Can you run 220g subs in the 308?
Going to look up loads tomorrow.
I use 185 grain bullets out of my 11.25 twist barrel and they stabilize just fine. I get about 1-1.25" at 100 yds. With trailboss you can shoot lighter bullets and keep subsonic with a bolt gun, no worries about cycling. The brass should just about last forever too considering the pressures.