Q&A: .30-Caliber Twist Rates

From the vault: A reader-submitted question about .30-caliber twist rates. As published in the October 2001 issue of Shooting Sports USA.

Q. Most .30-caliber barrels are 1:10 twist, and .30-caliber bullets range from 90 to 220 grains, what is the optimum twist rate to stabilize a 150-grain bullet?

A. The .30-caliber rifles and bullets are more forgiving when selecting barrel twist rate. Practically every rifle maker known today offers its .30-caliber barrels in either 1:10, or 1:12 twist. The 1:10 twist is the overwhelming favorite, but that may just be so primarily for simplification in the manufacturing processes. Remington, for instance, makes its .308 Win., .30-06 Springfield and .300 Winchester Magnum barrels all with a 1:10 twist. If you were considering using 200-grain or heavier bullets regularly in your .30-caliber rifle, we would suggest sticking with a 1:10 twist. If we were building a rifle to shoot best with 150-grain bullets, our choice would be 1:12 twist.

Submit your questions to shootingsportsusa@nrahq.org.

Lead photo of a Hawk Hill Custom Cut-Rifled .30-cal. barrel courtesy of Altus Shooting Solutions.