CMMG 55AC20AAB Banshee MK4 5.56 NATO 12.5" 31-Round Threaded Barrel Carbine

The CMMG Banshee MK4 5.56 NATO 12.5" carbine is a compact, purpose-built platform engineered for operators who demand versatility without compromising velocity or ergonomics. This short-barrel rifle (SBR) delivers the ballistic efficiency of intermediate-range engagements while maintaining the maneuverability required for tight-quarters tactics, vehicle operations, and home defense scenarios. The 12.5-inch barrel represents the optimal balance between velocity retention in 5.56 NATO and overall weapon length, making it ideal for law enforcement tactical teams, military support roles, and civilian shooters prioritizing compact firearm handling.

Built on CMMG's proven Banshee platform, this MK4 generation carbine features a fully threaded barrel accommodating suppressors, muzzle brakes, or flash hiders without permanent modification. The 31-round magazine capacity provides sustained firepower during extended engagements, while the short profile—weighing just 9.8 pounds—reduces operator fatigue during dynamic movement and precision targeting. The 5.56 NATO chambering ensures compatibility with military-standard ammunition inventories and delivers reliable, consistent performance across variable environmental conditions and engagement distances from close quarters to 400 meters.

Professional end-users including tactical operators, military personnel, and certified defensive shooters benefit from this carbine's responsive handling characteristics and predictable ballistics. The threaded barrel design accommodates sound suppression systems—essential for hearing protection in breaching operations and sustained firing drills—while muzzle devices manage recoil impulse and flash signature. Compliance with federal SBR regulations and proper registration is required in jurisdictions where applicable; confirm local and state requirements before purchase and transfer through a licensed FFL dealer.