The CMMG AR-15 Pistol Receiver Extension Kit (brand part number 55CA65A) gives builders everything needed to complete a pistol lower group in one package, pairing with any lower parts kit rather than requiring a separate buffer system purchase. CMMG includes its pistol receiver extension, a carbine buffer assembly, and a matching carbine action spring, along with a black-finished ambidextrous sling mount end plate so shooters can attach a sling on either side of the pistol. Built specifically to fit the AR-15 pistol platform rather than a full carbine or rifle-length build, it’s a straightforward, complete solution for finishing a pistol lower without sourcing each buffer system part individually.

Key Specifications

• Includes a CMMG pistol receiver extension.
• Includes a carbine buffer assembly.
• Includes a matching carbine action spring.
• Includes an ambidextrous sling mount end plate.
• Built specifically for the AR-15 pistol platform.
• Classified as a pistol/carbine conversion component set.
• Uses a carbine-style buffer system.
• Weighs approximately 0.57 lb for the full kit.
• Finished in Black.

Frequently Asked Questions

Does this include a lower parts kit? No, it’s designed to pair with your choice of lower parts kit to complete the build.

Can I mount a sling on either side? Yes, the end plate includes an ambidextrous sling mount.

Buy the CMMG AR-15 Pistol Receiver Extension Kit – Black, Ambi Sling Mount

Finish your AR-15 pistol build with a complete, matched buffer system. Order it from our CMMG lineup, part of our AR buffer system selection, at our Lubbock, Texas gun shop for fast, direct shipping.