Carbine barrel twist

[mousegunner]

I wanna shoot 69 to 75s out of a free floated AR carbine barrel on a new build I'm thinking about but what's a better twist 1-7 or 1-8 or don't matter?

 

[cmysix]

1-9 or 1-8

 

[Walt Krafft]

1-7 or 1-8 or don't matter? Don't matter is the answer.

 

[Ray123]

I Have to be different...for your application get a 1-8 twist Shilen match with ratchet rifling...it'll shoot 40 gr Nosler BT with military LC or range pickup brass into tiny groups. I Loaded the mag with 12 rds shot 11 shots into .594" at 100 yds the 12 rd was out of the group a little still less than an inch but I got complacent.. or the gun, who knows.. got some 85.5 Berger but haven't tried them yet, as I have about 10 other projects. If ya spend time on an AR and buy a quality barrel "in most cases," you can get 3 shots in one enlarged hole...5 shot .5" groups or less quite often...with most calibers. The 6mm ARC, 223, 300 Hamr, 300 blackout, 308 win, 6.5 Creedmoor are the easiest. The 224 Valkyrie was more difficult. Bolt carrier centering made a big difference in 224 Valkyrie and a 6 5 twist helped in mine...and the 8.6 Blackout, the impossible task...most difficult, getting some 50 yd accuracy finally ...no quality barrels and 3 twist too fast for general accuracy IMO but put it in an 8 twist, a better quality barrel it would shoot.

 

[JB10]

Im shooting 75gr out of a 1:8 just fine.

 

[ebb]

A 1 in 9 may work but it is not 100%. 1 in 7 or 1 in 8 for sure

 

[Kurz]

I wanna shoot 69 to 75s out of a free floated AR carbine barrel on a new build I'm thinking about but what's a better twist 1-7 or 1-8 or don't matter?

It will depend on the style or construction of which bullet. Those which are slightly longer because of the addition of a tip whether aluminum or plastic, can use a slightly faster twist rate (1:7.5") than the more standard hollow point. This provides a higher BC than with the slightly slower twist rate.

If you're just shooting paper and steel, you can make good use of the 1:8" twist rate. But if you change your mind and want to shoot some of the heavier long range bullets then you might consider a slightly faster twist rate.

See? It all depends.

 

[ragsflh]

1;8 twist