CMMG MK9 AR-9 9mm Luger Dedicated Lower Receiver Only, 7075-T6 Aluminum, Colt-Pattern, CAR-Style Stock
This CMMG MK9 is a dedicated 9mm AR-9 lower receiver only, built on a hard-anodized 7075-T6 aluminum receiver and configured for Colt-pattern magazines. It features AR-15 pattern controls with SAFE/SEMI selector markings, a fixed steel ejector pinned in the receiver, and a Colt-SMG style magazine release. The lower is complete with a telescoping CAR-style aluminum stock and a checkered polymer AR-pattern pistol grip. It is compatible with CMMG 9mm Radial Delayed Blowback uppers and is marked "CMMG, INC FAYETTE, MO USA" and "MK9."
Condition
Overall Condition: Poor condition.
Bore Condition: Not applicable; this listing is for a lower receiver only and includes no barrel.
Specific Condition Notes: There is heavy finish loss, scratching, and visible tooling marks from prior handling and use. The trigger shows grinding but still functions. The top trigger pin hole appears widened or drilled to the point that the pin moves when the trigger is pulled. Offered as a gunsmith special and sold as-is. Please refer to the photos for a closer look.
What’s Included
- CMMG MK9 9mm AR-9 lower receiver only (complete lower)
- Telescoping CAR-style aluminum stock with checkered metal buttplate
- Checkered polymer AR-pattern pistol grip
- Fixed steel ejector pinned in the receiver
- No upper receiver or barrel included
This MK9 lower is purpose-built for 9mm, using a Colt-pattern magazine interface and a fixed steel ejector pinned into the receiver. The dedicated design reflects the MK9’s roots in earlier straight-blowback AR9 configurations while remaining compatible with CMMG 9mm Radial Delayed Blowback uppers.
The receiver is 7075-T6 aluminum with a hard-anodized black finish. Controls follow the AR-15 pattern with SAFE/SEMI selector markings and a manual safety, and it uses a Colt-SMG style magazine release geared to Colt-pattern magazines.
The lower is outfitted with a CAR-style telescoping aluminum stock featuring a checkered metal buttplate, plus a checkered polymer AR-pattern pistol grip for a familiar control layout. Receiver markings include "CMMG, INC FAYETTE, MO USA" and "MK9."
Made in the USA, this lower receiver only listing is an option for those building or servicing a 9mm AR-9 using Colt-pattern magazines and CMMG 9mm uppers. Please review the condition notes and photos carefully.