CMMG 28B3D0CCT Endeavor 22 5.56 NATO 20" Rifle

The CMMG 28B3D0CCT Endeavor 22 5.56 NATO 20" Rifle is a purpose-built platform designed for shooters who demand accuracy, reliability, and modularity in a compact form factor. Built by CMMG—a manufacturer with deep roots in tactical and competition shooting—this rifle serves law enforcement trainers, military personnel, civilian marksmen, and budget-conscious shooters seeking a .22 LR conversion or dedicated rimfire trainer. The 20-inch barrel and lightweight 5.5-pound construction make this platform ideal for transitions between larger-caliber duty rifles, marksmanship fundamentals training, and extended practice sessions where ammunition costs matter.

This rifle chambered in 5.56 NATO combines CMMG's Endeavor series engineering with a 20-inch barrel that balances velocity, control, and handling in mid-range distances. The Endeavor platform is known for its modular design philosophy, allowing users to swap components and optimize the rifle for different mission profiles without requiring specialized tools. At 5.5 pounds unloaded, the rifle remains controllable during extended shooting drills while maintaining the ergonomic profile and controls familiar to AR-platform operators. The compact 38.1-inch overall length reduces fatigue during transport and tactical movement, making it suitable for vehicle-based operations and confined spaces common in law enforcement and military training scenarios.

The CMMG 28B3D0CCT Endeavor 22 benefits shooters who prioritize cost-per-round training and skill maintenance without sacrificing platform familiarity. Law enforcement academies use similar configurations for qualification rounds and fundamental drills, while competitive shooters leverage the modularity for stage-specific configurations. Military units employ this class of rifle for marksmanship sustainment and low-ammunition-cost training cycles. The AR-pattern compatibility ensures that standard furniture, rails, and optic mounts interface seamlessly, allowing operators to transfer muscle memory and setup knowledge across their duty and training arsenals. Installation and maintenance follow conventional AR-15 procedures, making field-stripping and cleaning straightforward for users already proficient with the platform.