Barrel: 8.5" 4150V Chrome Moly vanadium steel is chambered in .338 ARC with a 1 in 8" twist. The Nitride pistol-length gas barrel is finished off with a PSA 7" Lightweight Hex M-Lok Rail, a .750 low profile gas block, and an A2 Flash Hider.Upper: Forged 7075-T6 A3 AR upper is made to MIL-SPECS and hard coat anodized black for durability. Featuring a mil-spec finish, these uppers are made for us right here in the USA by a mil-spec manufacturer.Bolt: Full-auto profile bolt carrier group. 9310 steel bolt, Shot Peened, Gas Key Hardened to USGI Specifications, Fastened with Grade 8 screws, and Staked Per Mil-Spec. 8620 steel M-16 profile carrier is nitride treated.Included: Duramag 338 ARC 10Rd Magazine Buy 338 ARC Ammo