The CMMG Banshee Mk4 (CMMG part no. 54A3B0FAB) shrinks the 5.7x28mm AR pistol down to an ultra-compact 5-inch barrel, making it one of the most maneuverable options in the lineup. 5.7x28mm has earned a reputation as an effective personal-defense cartridge, offering noticeably less recoil than 5.56mm at close range while still cycling reliably off a standard AR15 lower. Shooters who prefer a fixed-magazine-well AR over pistol-caliber designs will appreciate that this Banshee is built on CMMG’s Mk4 platform, keeping it compatible with the wider AR ecosystem. It’s finished in CMMG‘s armor black for a tough, understated look.
Key Specifications
- Chambered in 5.7x28mm, prized as a low-recoil, close-range personal-defense cartridge.
- Runs an ultra-short 5-inch barrel for maximum maneuverability in tight spaces.
- Holds 32 rounds per magazine for a deep supply of ready ammunition.
- Built on the Mk4 platform with a standard AR15 lower receiver rather than a proprietary design.
- Cycles off a radial delayed blowback operating system tuned for the 5.7x28mm cartridge.
- Runs a CMMG Zeroed linear compensator muzzle device to help control muzzle rise.
- Wears a CMMG EML M-LOK handguard for a full-length accessory mounting surface.
- Features an ambidextrous safety selector for fast manipulation from either side.
- Ships optics-ready with no fixed sights, leaving the top rail open for a red dot.
- Weighs approximately 4.6 pounds unloaded, keeping the package light and easy to carry.
- Finished in armor black for durability and a low-glare exterior.
Frequently Asked Questions
How compact is this pistol? Very — it runs a 5-inch barrel, one of the shortest in the Banshee Mk4 lineup, for maximum maneuverability.
Is it built on a standard AR15 lower? Yes, the Mk4 platform uses a standard AR15 lower receiver rather than a pistol-caliber-specific design.
Is this pistol optics-ready? Yes, it ships with no fixed sights so you can mount a red dot directly to the rail.
Buy the CMMG Banshee Mk4 Pistol, 5.7x28mm, 5-Inch, Armor Black
For shooters who want the smallest possible footprint without giving up AR ergonomics, this 5-inch Mk4 Banshee is hard to beat. Low recoil, high capacity, and true AR15 compatibility make it a versatile choice for defense or the range. Order it from our AR pistols lineup at our Lubbock, Texas gun shop for fast, insured shipping to your FFL.
