The Rock River Arms LAR-BT3 X-Series X-1 XBT31750B.V1 is a high-performance, direct-impingement AR-10 platform rifle. Chambered in .308 Winchester / 7.62x51mm NATO, it features an 18-inch fluted, cryogenically treated stainless steel fluted barrel and an Operator A2 fixed stock. Includes (1) 20rd magazine and rifle case. FEATURES CALIBER: .308 / 7.62x51mm NATO Chamber LOWER RECEIVER: RRA LAR-BT3 Billet Lower UPPER RECEIVER: RRA LAR-BT3 Billet A4 Upper, Extended Charge Handle Latch BARREL: 18" Fluted Stainless Steel, 1:10 Twist, Cryogenically Treated MUZZLE DEVICE: RRA Hunter Muzzle Brake / 5/8-24 TPI GAS BLOCK: Low Profile Gas Block, Mid-Length Gas System TRIGGER: RRA Two Stage Ultra Match Varmint Trigger BUTTSTOCK: RRA Operator A2 Stock w/ Sling QD Ports PISTOL GRIP: Hogue(R) Rubber Grip HANDGUARD: RRA 17-inch Lightweight Free Float Rail, M-LOK(R) Compatible Length: 40.5 Inches Accuracy: 1 MOA at 100 yards