CMMG 55B8D86AB Dissent MK4 5.56 NATO 10.5" Rifle

The CMMG 55B8D86AB Dissent MK4 5.56 NATO 10.5" Rifle is purpose-built for operators and civilians demanding a compact, duty-ready platform without compromising on performance or reliability. This short-barreled rifle (SBR) excels in close-quarters environments—vehicle operations, home defense, and tactical training—where maneuverability trumps long-range precision. CMMG's Dissent line has earned respect in both military contracting and law enforcement circles for delivering modular design, proven ergonomics, and field-proven durability under sustained fire.

The 10.5-inch barrel optimizes velocity and handling balance while maintaining the 5.56 NATO's intermediate-range terminal performance—critical for CQB scenarios where overpenetration liability and collateral damage must be managed. At 5.21 lbs unloaded, this rifle cycles fast enough for rapid target transitions and responds predictably to suppressors and compensators, thanks to CMMG's optimized gas system tuning. The Dissent MK4 platform integrates mil-spec Picatinny rails for optics and accessories, modular fire control group architecture for customization, and a gas tube design that supports both suppressed and unsuppressed fire without reliability loss—a feature critical for operators deploying with variable audio signature requirements.

Tactical professionals, home defenders, and serious shooters building a specialized rifle for confined-space work will find the Dissent MK4 5.56 NATO 10.5" platform delivers the modularity and performance expected from a modern short-barreled rifle. Proper registration as an NFA firearm is required in most U.S. jurisdictions (SBR tax stamp and Form 1 or Form 4 compliance). Magazine compatibility, rail-mounted systems, and aftermarket component support are extensive across the AR-pattern ecosystem, allowing users to tailor sight systems, stocks, grips, and muzzle devices to mission requirements.