07 February 2012, 03:55
tsturmBarrel twist for AR
What is a good twist rate for 50g to 62g projectiles in my AR. 1: 7,8 or 9???
Thanks

07 February 2012, 04:17
FjoldIf I was only going to shoot 62 grain and lighter I would go with the 1:9" twist.
08 February 2012, 04:25
viperidae1/7 or 1/9 will both work fine. The 1/7 is really only needed if shooting long projectiles. I don't remember why but length factors into stability (needing a tighter twist) and twist more then weight. If using over the counter ammo I would probably go with 1/9, 1/7 if it was the same price but I wouldn't pay $1 more for it.
08 February 2012, 07:28
tsturmquote:
Originally posted by viperidae:
1/7 or 1/9 will both work fine. The 1/7 is really only needed if shooting long projectiles. I don't remember why but length factors into stability (needing a tighter twist) and twist more then weight. If using over the counter ammo I would probably go with 1/9, 1/7 if it was the same price but I wouldn't pay $1 more for it.
Thanks guys!!
08 February 2012, 07:35
kcstott1-9 will be more versatile. I had an AR with a 1-7 and it refused to shoot 55 gr with any kind of accuracy.
Bump up to 62 gr or 69 sierra match kings and she was a one hole hole rifle. And that was FN HBAR A2 stock and hand guard not floated. With iron sights.
Oh did I mention that group was shot with 22 year old eyes
Now I have a M4 style rifle 16" bbl and it is damn accurate too. 1-9 twist so we can shot everything but the longest 69 gr and up stuff.