Green Mountain Barrels has 45 cal barrels in 1:16 twist, which is better for heavy subs than the typical 1:24 twist. However, you have to approach published reload data, that are usually for 1:24 barrels, with caution (as you always should).
Most factory bolt guns are 16 twist now that's all we use in the 450's . I might check around for a faster twist yet just to experiment with we did that with the 350 legend and use 10 twist barrels now .
