my rifle has a 1 in 12 twist, its a custom rifle built on a savage action with a 24 1/4 inch heavy barrel with a competition crown made by a friend of mine. with a few other extras like a jarden trigger set at 1lb 8 oz choate ultimate varmint stock, custom desert camo paint job pretty sweet rifle, its a .5 MOA rifle easy. it does great with 60 grain v-max bullets just they arent very explosive on impact at long ranges say in excess of 300 yards. the reason i like the TNT's is speer claims they will have explosive expansion even at velocities as low as 1800 fps.