Brownells AR-15/M16 Barrels, made for Brownells by Satern Barrels, feature 5R button rifling and are machined from 416R gun barrel steel for a superior shooting barrel. These .308 Winchester DPMS pattern barrels feature a Black Nitride finish, for superior lubricity and corrosion resistance (24” barrel is stainless steel). Barrels have a 1-10 twist, for excellent performance with a wide range of bullets. Available in 16” and 20” lengths. Muzzle is threaded for 5/8-24 and the gas shoulder accepts .750 gas blocks. Opposite side of gas port features dimples, so that gas block set screws are secured in place, preventing movement.
AR-15, Issue:11, Page:018
Big Book Catalog, Issue:70, Page:016
Sinclair, Issue:5B, Page:248