300BlkTalk

Howdy all,

I am trying to decide on what lenght barrel to include in my future build. I understand the 300 blackout is designed mainly as a pdw round, however I do enjoy shooting distances.

Does a 9 or 10 in barrel maintain sub 2 moa accuracy at 300 yards? How does it compair to a carbine and rifle lenght barrel? I ask because I want to go SBR with suppressor, but I do want to be able to reach reliably when needed.

Thanks for the help

Your barrel length has very little to do with accuracy. Just pick a good quality barrel, or blank if you will have it custom built, and choose the appropriate bullet weight for the rifling and it should be fine.

All of the 16 inch barrels we have tried have been significantly more accurate than the short barrels for supersonic bullets. For subsonic it does not seem to matter much.

Alot of times short barrels can even outdo long barrels due to having more regidity. Barrels are voodoo.

Yeah, a 16 can outshoot a 26 but it is hard for an 8 to outshoot a 16.

But I have a 7" barreled 7.62x39 rifle that will put wolf 123 grain FMJs in a quarter all day long at 100 yards. I have never ceased to be impressed with that thing.

Robert, do you have any idea/theory as to why the Subsonic 300 Blackout is more accurate than the Supersonic out of the shorter barrels?

regidity, harmonics, drag, on and on. Almost every Encore or contender I have shot is more accurate as a pistol.

I think that the higher muzzle exit pressure of supersonic ammo, and the higher pressure of short barrels, flips the bullets off at an angle. It seems to effect boat-tails more than flat base, and shorter bullets are not effected as much.

As for quarter-size groups - our 9 inch barrels can do 1.25 inch 5-shot group averages, which is larger than a quarter, but still ok.

That sounds more than good enough for the weapon's intended purpose. I was quite impressed by the sound, or lack thereof, at the shoot of your 300 Blackout Subsonic round. Wish I would have talked to you a bit more, but wasn't sure it was you until later.

I've been amazed at the accuracy that I'm getting with my 10' Noveske barrel both with subs and light, flat based super sonic rounds.