The Mk47 AKS13 is one of CMMG newest Mk47 upper groups and features the Krink muzzle device pinned and welded to a 13″ barrel to meet the 16″ legal requirement. Additionally it features a pinned on gas block for improved reliability. The Mk47 AKS8 features CMMG’s mid-sized receiver based on the Mk3 platform, carved from billet 7075-T6 aluminum. The Mk47 was designed to harness the power and reliability of the 7.62x39mm cartridge utilizing a robust bolt based off CMMG Mk3 (.308). Every upper comes equipped with a Krink muzzle device, Pinned gas block.