CMMG 99DE642 Replacement Barrel Kit with Bolt Carrier Group 9mm Luger 16.10″ Threaded Black Radial Delayed Blowback Fits AR-Platform

CMMG’s 9mm Barrel and BCG Kit allow you to build a Pistol Caliber Carbine using CMMG’s Patent Pending Radial Delayed Blowback System. Unlike typical direct blowback systems 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. Their Barrel and Bolt Kits are designed to work exclusively with mil-spec AR-15 upper receivers with a modified ejection port like their MkG/MkGs upper and most mil-spec AR15 lowers when used with 9 AR Conversion mags as well as their MkGs Mk17 and Mk9* lowers. Other manufacturers receivers may work but we cannot guarantee function or reliability.*Older Mk9 lowers will require one of their retrofit kits to convert it to a Radial Delayed Blowback compatible lower instead of Traditional Blowback.