CMMG 9mm AR Pistol, 5-Inch Threaded Barrel

Description

The Banshee MK4 is CMMG’s compact AR-platform pistol built around the 9mm cartridge, and it fits a specific role well: a short, handy firearm suited to home defense, range work, and suppressor use. The five-inch barrel keeps the overall package tight, and because 9mm is a straight-blowback-friendly cartridge with lower pressure than rifle rounds, CMMG uses a radial delayed blowback system on the MK4 — a design that slows the bolt’s rearward movement by having the bolt head rotate slightly before unlocking. That delay absorbs a meaningful portion of the felt impulse that a pure blowback design would send directly to the shooter, making the MK4 noticeably softer to run than a conventional blowback 9mm AR pistol of the same size.

The barrel carries a 1/2×28 thread pitch, which is the standard for 9mm suppressors and muzzle devices, so there is no need for an adapter. The optics-ready upper has no fixed sights installed, leaving a clean top rail for whatever red dot or magnified optic suits the intended use — at this barrel length, a compact red dot is the natural choice. Ambidextrous controls mean the safety and other key functions are accessible from either side without modification. The receiver and pistol grip are finished in Tungsten Cerakote, a muted gray-toned coating that resists corrosion and wear. A 30-round magazine ships with the pistol, giving substantial capacity in a format that feeds directly from standard GLOCK-pattern magazines, which simplifies sourcing spares.