MK116 Compound Specs: The Compound rifle is a combination of a Mod 1 upper with the Mk1 Mod 2 Lower – Operating System: PWS Long Stroke Piston System 3 setting Adjustable Gas Regulator – Caliber: .223 Wylde – Barrel Length: 16.1 – Gas System Length: Mid-Length – Barrel Twist Rate: 1:8 – Muzzle Velocity: 2980fps – Muzzle Device: PWS FSC 556 – Upper Receiver: PWS Proprietary Piston Upper T6 7075 Forged Anodized – Handguard: PWS M-Lok 15.05 Handguard (1.7 width 2.25 height) – Charging Handle: Radian Raptor Ambidextrous Charging Handle – Lower Receiver: PWS ambidextrous MK1 MOD 2-M Multi-Caliber Lower T6 7075 Forged Anodized AR-15 Compatible – Trigger: Mil-Spec Enhanced PTFE Coated. – Trigger Pull Weight: 5.5-6.5 lbs. – Buffer Tube: PWS Enhanced Buffer Tube with ratchet lock castle nut and end plate set with built-in QD mount – Buffer: PWS Enhanced H2 Steel Body Buffer – Furniture: Bravo Company USA® Buttstock and Pistol Grip