Brownells Brownells Brownells 75th Anniversary - A Shooting Heritage

Locks Bolt Open After Last Round; Preserves Bolt Catch Button Function

Drop-in parts for rifles fitted with a CMMG or Atchisson-style .22 LR conversion kit work with the existing bolt catch to lock the bolt to the rear after the last round is fired. Molded polymer Bolt Hold Open Actuator fits into the top of the magazine well to precisely align a CMMG 25-round .22 LR magazine for reliable bolt lock open. Alignment can be further fine-tuned by adjusting the actuator’s steel bolt-stop plate with the included hex wrench. No permanent rifle modifications required; simply lift out the actuator to return to shooting centerfire ammo.

This requires the use of a CMMG brand magazine called the "Evolution Magazine".


AR-15, Issue:09, Page:007
Big Book Catalog, Issue:66, Page:007
New Product Supplement, Issue:641, Page:019

SPECS: Molded polymer body, black. 1018 carbon steel catch. 2½" (6.3cm) long, 15⁄16" (2.4cm) wide, ¾" (1.9cm) high. ½ oz. (14g) weight. Installation instructions and wrench included.

CMMG - AR-15 .22 LR BOLT HOLD OPEN ACTUATOR