Description
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”)


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