The CMMG Buffer Assembly, Carbine, AR15 (brand part no. 55CA977) is the carbine buffer for an AR15 recoil system. CMMG designs it to work with the AR15 Carbine Action Spring and with M4 or carbine-length buffer tubes. It also works with CMMG’s Fastback Receiver Extension. The buffer meets or exceeds mil-spec. A complete carbine buffer tube kit is also available from CMMG for builders who need the tube as well.

Key Specifications

• The part is a carbine buffer for the AR15 platform.
• It works with M4 and carbine-length buffer tubes.
• It also works with CMMG’s Fastback Receiver Extension.
• It must be used with the AR15 Carbine Action Spring.
• The buffer meets or exceeds mil-spec.

Frequently Asked Questions

What do I need to use with this buffer? CMMG says it must be used with the AR15 Carbine Action Spring and with M4 or carbine-length buffer tubes, or with its Fastback Receiver Extension.

Is this a complete buffer tube kit? No. This listing is the buffer assembly only. CMMG sells a complete Carbine AR15 Buffer Tube Kit separately.

Buy the CMMG Buffer Assembly, Carbine, AR15

The buffer is a small part that sets how an AR cycles, and CMMG builds its carbine version to mil-spec. It pairs with M4 or carbine-length tubes and the matching action spring. Order it from our Lubbock, Texas gun shop for fast, direct shipping, and browse more AR buffer system parts while you are here.