Preview: CMMG Barrel and BCG Kit In .45 ACP

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posted on January 5, 2022
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CMMG Barrel

Established in 2002, CMMG continues its innovative engineering by providing DIY kits to at-home builders of AR-15-type guns. Whether building from scratch, or converting previously built guns into custom works, hobbyists and professionals alike benefit from the unique engineering CMMG Inc. has to offer. The MkG 8" Barrel and BCG Kit presents the DIY gun-builder with a pistol-caliber option for AR-15-type systems that utilizes a highly sought-after, big-bore chambering: .45 ACP.

With a patent pending design, the Barrel and BCG Kit converts the conventional gas-operated AR-15 action. The adaptation is relatively simple and requires fewer parts than Stoner's original action design. The combination that CMMG created, increases reliability of semi-automatic pistol cartridges and combines to help reduce overall weight and fouling, making for a lightweight, clean- and cool-running action.

CMMG’s Radial Delayed Blowback (RDB), though patent pending, completely alters system functionality. Rather than routing burnt propellant into the action, CMMG’s RDB system harnesses energy from the fired cartridge case to initiate a delay and blowback sequence that, in design, maintains semi-automatic function with improved mechanics. Previous American Rifleman testing has confirmed the RDB system’s ability to provide repeatable performance.

The MkG 8" Barrel and BCG Kit chambered for .45 ACP gives gun builders a 4140 chrome-moly-steel barrel with a 1:16" twist rate and a .578x28 TPI threaded muzzle. In addition to the barrel, the kit’s bolt carrier group is configured to employ the company’s Radial Delayed Blowback operating system. This kit is designed to function without modifications in MkG lower receivers and mil-spec uppers. Retail pricing for the MkG 8” Barrel and BCG kit is set for $399.95. It is important to note that CMMG is a build-to-order company and supply chain deficits may impact purchase orders.

In addition to 8” kits designed for .45 ACP, CMMG offers kits in 9 mm Luger and .40 S&W with barrel lengths from 5” to 16”. All NFA rules apply. To learn more, please visit cmmg.com.

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