CMMG Radial Delayed AR-15 Bolt Carrier Group 9mm Luger 8" Medium Contour 1:10" Twist Nitride

The CMMG MkG GUARD Barrel and BCG Kit allow you to build a Pistol Caliber Carbine using the Patent Pending Radial Delayed Blowback System. Unlike typical direct blowback systems, this RDB uses a bolt that is forced to rotate and unlock, slowing the BCG. This results in a lighter BCG for a lighter rifle, and less felt recoil than a straight blowback system. CMMG MkG Barrel and Bolt Kits are designed to work exclusively with CMMG MkG Lowers, and a mil-spec upper receiver with enlarged ejection port. Other manufacturers' receivers may work, but we cannot guarantee function or reliability. FeaturesSalt Bath Nitride Finish inside and outRadial Delayed Blowback Bolt (Patent Pending)Requires enlarged ejection port for reliable operation