CMMG Dissent BR4 5.56x45mm 16.1in 10rd Midnight Bronze Rifle (55A520B-MB)

The CMMG Dissent BR4 5.56x45mm 16.1" Rifle delivers a refined blend of classic ergonomics and modern engineering in a sleek carbine built to perform. Chambered in the ever-popular 5.56x45mm, this BR4 is designed for shooters who want extended reach, flat-shooting performance, and versatile application across hunting, sporting, and training environments. Its 16.1-inch MT-contour barrel, crafted from 4140CM steel with a resilient SBN finish and paired with a fast 1:7 twist rate, offers excellent stabilization across a wide range of bullet weights.

At the heart of the rifle is CMMG's compact direct-impingement operating system, tuned through a mid-length gas port and an adjustable 0.750-inch gas block that allows shooters to precisely dial in performance for specific ammunition or suppressed use. The threaded muzzle (1/2 x 28) is capped with a CMMG ZEROED muzzle brake, delivering controlled recoil management and flatter follow-up shots. The Dissent 7075-T6 aluminum upper receiver pairs seamlessly with the BR4 billet 7075-T6 aluminum lower, forming a rigid, lightweight foundation.

The lower receiver is compatible with Remington 870-style stocks, and comes equipped with a Magpul SGA stock, offering a classic shoulder feel, adjustable length of pull, and confident control.

User-focused features round out the package, including a left-side Dissent side-charging handle for smooth manipulation, a ZEROED drop-in single-stage trigger for a crisp, predictable break, and an integrated trigger guard for clean ergonomics. The reversible cross-bolt safety selector supports flexible operation, and the rifle ships with two Magpul 10-round PMAGs.