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Overview
The CMMG 5" .40 S&W MkGs Barrel and BCG Kit lets you build a pistol caliber carbine using CMMG’s Patent Pending Radial Delayed Blowback (RDB) system.
Unlike typical direct blowback systems, the RDB uses a bolt that is forced to rotate and unlock, slowing the BCG. This results in a lighter BCG and less felt recoil.
Fitment
Designed to work exclusively with CMMG MkGs lowers. Other manufacturers’ receivers may work, but function and reliability are not guaranteed.
All NFA rules apply.
All CMMG products come with a Lifetime Quality Guarantee.
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