The CMMG .22LR AR Conversion Kit takes a 5.7x28mm to rimfire.

In January, Ruger launched the Ruger-57, reigniting interest in the 5.7x28mm cartridge. Since then, the market continues to add more products devoted to 5.7x28mm. In February, for example, CMMG a conversion kit, turning an AR rifle into a 5.7. Now CMMG comes back with a rimfire in its new .22LR AR Conversion Kit.

CMMG .22LR AR Conversion Kit

The CMMG .22LR AR Conversion Kit converts a CMMG 5.7x28mm upper receiver group to .22 LR. The kit swaps out the bolt carrier group. It pairs a 5.7x28mm upper and any Mil-Spec AR lower. A dedicated CMMG .22 LR magazine comes with the kit as well.

The Mk57 .22LR Conversion Kit works with all CMMG Mk57 5.7x28mm upper receiver groups and bolt/barrel combinations. It pairs with any Mil-Spec AR-15 lower receiver. CMMG also offers Mk57 5.728mm complete uppers in 5-, 8- and 16-inch barrel lengths.

Converting an upper to .22 LR reduces cost for high-volume shooting for long days training at the range. It also reduces recoil and muzzle flash. For both training and introducing new shooters, conversion kits deliver tremendous utility.

The Mk57 .22LR Conversion Kits come with a dedicated bolt carrier group and the choice of one or three 25-round magazines. The kits retail from $199.95 to $229.95.

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