NRA Gun of the Week: CMMG Mk57 Banshee

American Rifleman Staff

posted on November 17, 2018

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Most who know the 5.7x28 mm cartridge don’t know that CMMG Inc., a U.S. manufacturer, is chambering an AR-pistol to operate the Belgian-designed “Five-Seven” cartridge. The Mk57 Banshee pistol, featured here, operates different than the typical Stoner, gas-operated design. This Slate Gray-Cerakoted, 4 1/2-lb. pistol, built from both forged and billet aluminum, utilizes a delayed form of cartridge blowback termed "radial-delayed" by the manufacturer. To find out more, watch this week's NRA Gun of the Week video hosted by Kelly Young.

Specifications:
Model: Mk57 Banshee
Manufacturer: CMMG Inc.
Chambering: 5.7x28 mm
Action Type: radial-delayed, blowback-operated center-fire pistol
Lower Receiver: 7075-T6 billet aluminum
Upper Receiver: 7075-T6 forged aluminum
Barrel: 5”; threaded 1/2x28 TPI, includes thread protector
Trigger: 5-lb, 7-oz. pull
Finish: Cerakote, Slate Gray
Magazine: 20-round detachable box
Weight: 4 lbs., 9 ozs.
MSRP: $1,550

Additional Reading:
SHOT Show 2018: CMMG Mk4 DTR2 .224 Valkyrie Rifle
Tested: CMMG MK4 Banshee .22 LR Pistol
Tested: CMMG Guard Pistol Caliber Carbines
Tested: CMMG MkW-15 XBE Anvil

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