AR15 BCG- 224 Valkyrie/ 6-8 SPC Left Hand, Nitride

Left Hand AR-15 bolt carrier group for AR-15 upper receivers only. Calibers supported: 224 Valkyrie, 6.8 SPC, 338 Spectre. - M16 Auto Profile Carrier machined from aircraft/bearing quality 8620 steel, properly heat treated, ground to perfection, Black Nitride finish by H&M - Bolt machined from a single piece aircraft/bearing quality 9310 steel, heat treated properly, precision ground, shot peened and MPI'd - Firing pin machined to the mil-spec print from 8740, precision ground, and chrome plated - One Piece Billet Fully Machined Enhanced Extractor, phosphate coated for increased reliability and corrosion resistance - Nitride Cam Pin - S7 tool steel ejector and extractor retaining pin - 4130 Gas Key, nitride, precision staked using our hydraulic staking machine - KAK Carrier Key Screws - T25 drive, Grade 8, properly heat treated