- .300 AAC Blackout caliber
- This upper is designed to work with any standard AR15 lower
- Direct impingement operating system
- 4140CM, SBN barrel material
- Carbine gas port location
- Cmmg EML15 M-lok hand guard
- Mk4 Zeroed parts and accessories – Quality comes standard
- Cerakote standard finish
- Lifetime Quality Guarantee
Originally created for use in subsonic/suppressed applications, .300 BLK has evolved into a very capable caliber, available in a variety of subsonic and supersonic loadings. Whether it’s hunting, personal defense, or target shooting, this Cmmg Resolute Mk4 300BLK 16.1″ Upper Group (30B12BB) is just the thing to finish your next carbine build. This upper is designed to work with any standard AR15 lower.
Available in seven different Cerakote finishes, all Cmmg Upper Groups come complete with bolt carrier group and Zeroed accessories including: ZEROED AR15 Polymer Dust Cover, ZEROED AR15 Ambi Charging Handle, ZEROED Muzzle Brake .308.
