CMMG RESOLUTE MK4 .300 Blackout 14.5" Reciprocating charging handle Carbine

The CMMG RESOLUTE MK4 .300 Blackout 14.5" reciprocating charging handle carbine is purpose-built for operators and shooters who demand a dedicated subsonic platform with practical ergonomics and reliability in compact form. Chambered in .300 Blackout, this rifle excels in noise-reduced applications where suppressor performance is critical—a caliber that has proven itself across military special operations, law enforcement breaching teams, and civilian tactical professionals seeking quiet, effective medium-range capability.

The 14.5-inch barrel provides excellent velocity for subsonic ammunition while maintaining the handling advantages of a short-stroke design, making this carbine ideal for confined spaces, vehicle operations, and rapid target transitions. CMMG's design philosophy centers on the reciprocating charging handle—a feature that reduces bolt carrier tilt and gas tube stress compared to traditional non-reciprocating systems, enhancing long-term reliability under sustained fire. The MK4 platform utilizes a direct impingement operating system optimized for .300 Blackout ballistics, delivering consistent cycling with both supersonic and subsonic loads.

At an actual weight of 8.2 lbs, the rifle balances firepower with maneuverability; the compact 41-inch overall length accommodates tactical slings and vehicle carry while maintaining a natural cheekweld and sight picture. This carbine accepts standard AR-15 compatible furniture, magazines, and suppressor adapters, allowing seamless integration into existing setups. Whether for tactical operations or recreational shooting, the CMMG RESOLUTE MK4 is designed to meet the needs of modern shooters.