CMMG’s MkGs Barrel and BCG Kit allow you to build a Pistol Caliber Carbine using their Patent Pending Radial Delayed Blowback System. Unlike typical direct blowback systems, our 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 their MkG Lowers, and a mil-spec upper receiver with enlarged ejection port. Other manufacturers’ receivers may work, but CMMG cannot guarantee function or reliability.

• Barrels are 5″ Medium Taper or 8” Medium Taper
• 1:10 Twist
• 4140 Chrome Moly
• Salt Bath Nitride Finish inside and out
• 9×19 NATO Chamber
• Threaded 1/2-28
• Radial Delayed Blowback Bolt (Patent Pending)
• Requires enlarged ejection port for reliable operation.
• Weight: 1.4lbs(5”) and 1.7lbs(8”)