Centurion Lightweight Hammer Forged Barrel, Carbine 12.5" The Centurion Arms cold hammer forged 5.56 AR-15 barrels are made from high quality 41V50 Chrome Moly Vanadium—steel specifically designed for machine gun barrels—so you know it will last thousands of rounds. In order to get the 1:7 twist... MSRP: Was: Now: $299.99 Add to Cart