Twist rate .223 AI?

[FN in MT]

What's a good twist rate for a .223 AI that is intended for LR with 69 to 75/77 gr match slugs. But the owner wants to occasionally be able to shoot some 55 gr varmint slugs as well. I suggested a 1 in 8" or 1 in 9".

I'm no expert so figured I'd ask here.

 

[jpretle]

1-8 will give you the 80g bullet option, as well as handle the rest. A twist that quick may well chew up the jackets on some varmint bullets, however. Velocity may contribute, as well.
Don't think you can get by w/ 1-9 on the 80g's.

 

[FN in MT]

NO mention of anything heavier than 77 gr.As I think he already got a mess of 75 gr match slugs, SMK's maybe? And as he is running a can, only doing a 22" barrel so the velocity shouldn't be too high.

FN in MT

 

[varmintshooter]

I went with 1-8 and it shoots the 75 amax great. I also have a 1-9 (really 1-9.5) and it won't shoot the 75's at all. Go with 1-8 and you will be good.

 

[FN in MT]

As always, greatly appreciate the learned advice.