Fast 300BLK barrel twist rates

[Bummedic]

I'm seeing some manufacturers now making 1:5 twist barrels for 300BLK. Why so fast? What're the advantages or disadvantages? Thanks, and sorry if this has been discussed. My search really hasn't turned up much.

[rjacobs]

ultra short barrels too is my guess, 4-6" barrels. Trying to get 1 turn out of the projectile before it exits the barrel for stability.

Currently there are NO projectiles that will not stabilize in a 7 twist, 8" or 9" barrel. MOST suppressor companies will warranty their cans with 300blk down to ~8".

I know there have been a few 6" barrels being released and I believe had a faster than 7 twist. I also think the Sig MCX is 6 twist.

[Bummedic]

Mine is a Sig M400 300BLK upper with a 9" 1:5 twist barrel.

[jethroUSMC]

Companies being overly cautious to stabilize the heavier bullets? I remember a forum post by Robert Silvers (Developer of the 300BLK for AAC) saying that 1:7 twist for subs and supers down to a 1:9 twist out of as short as a 9-9.5" barrel.

[Bummedic]

I haven't read anything regarding the purposes for going so fast, but I'm guessing that a lot goes into R&D for these things and twist rates of 1:5 or 1:6 have to have a good reason behind them.

[MJN1957]

I'm guessing that a lot goes into R&D for these things and twist rates of 1:5 or 1:6 have to have a good reason behind them.

Not totally disagreeing with you, but never forget that there is always an accountant on any R&D team. The accountant has one responsibility: Determine if the entity funding the development can make money by producing it!

Since there doesn't appear to be a problem with the 'traditional' twist rates for 300 BLK (1-7, -8, -9) with the currently available bullet weights, one of two things could be at play;

Someone has a 'game changer' projectile that really needs the faster twist and is motivating the barrel makers to produce for it to create an installed-base large enough to make their projectile profitable quickly...

...or...

Someone is trying to make a market for themselves by creating an immaterial differential with their products to make a trend that only they can fulfill right now by exploiting the "I gotta have it now!" crowd.

[themonk]

1 in 8 is the SAMMI spec although I would not buy anything under 1 in 7. If you want to go short and run a can I would recommend a faster twist for stability.

[1slow01Z71]

My 6" 7twist stabilized long ass 208 amaxs just fine down to 850fps which is slow as hell while I tuned my sub load. I wouldn't worry about a super fast twist.

[themonk]

My 6" 7twist stabilized long ass 208 amaxs just fine down to 850fps which is slow as hell while I tuned my sub load. I wouldn't worry about a super fast twist.

208 is not that heavy for subs and is on the light side.