CMMG Pistol Banshee MK57 Semi-Auto 5.7x28mm 8" Barrel (1)-20Rd Magazine No Sights Polymer Grips Bronze Finish

FN Five-seveN pistol owners can rejoice, theres a new way to put your magazines to use. 5.7x28mm has quickly become the personal defense weapon caliber of choice for many. Offering near .22 LR levels of recoil and performance that rivals 5.56mm at close range its no surprise why. Even with a 5 barrel this BANSHEE sacrifices nothing when it comes to features. The Mk57 platform is designed to use FN Five-seveN pattern magazines and still offers the full range of AR15 operational features like last round bolt hold open and can utilize standard AR15 triggers. Available in a range of cerakote finishes, the BANSHEE series represents the most innovative AR pistols and SBRs available today. From the stylized receivers and EML handguards, every BANSHEE is tailor-made to be the personal defense weapon you can always depend on. EML7 handguards feature M-LOK slots at 3, 6, & 9 oclock positions and a full length picatinny top rail for accessories as well as an integrated handstop.

Mk57 ZEROED parts and accessories – Quality comes standard

The AR platform is well known for its capability for customization but picking the right parts doesn’t have to be a nightmare of homework. The full kit of ZEROED parts and accessories are made here in the USA with quality and attention to detail that is second to none and each BANSHEE comes equipped with a slew of ZEROED parts standard, including :

ZEROED Pistol Grip



ZEROED 60°/90° Ambi Safety



ZEROED AR15 Ambi Charging Handle



ZEROED AR15 Bolt Catch



ZEROED AR15 Polymer Dust Cover



ZEROED Linear Compensator 5.56mm



Platform Mk57

Caliber 5.7x28mm

Operating System Radial Delayed Blowback

Barrel Length 8

Barrel Twist 1:9

Barrel Contour Mt

Barrel Material 4140cm, Sbn

Barrel Twist 1:9

Muzzle Device Cmmg Zeroed Linear Compensator

Muzzle Thread 1/2 X 28

Gas Port Location N/a

Gas Block N/a

Upper Receive R Billet 6061 T6 Aluminum

Lower Receiver Mk57 Forged 7075 T6 Aluminum

Hand Guard Cmmg Eml7 M-lok

Finish Cerakote Standard

Charging Handle Cmmg Zeroed Ambi

Pistol Grip Cmmg Zeroed Pistol Grip

Buffer Type Carbine

Receiver Extension Cmmg 6 Position Fastback Extension

Stock / Brace: None

Trigger Type Mil-spec Single Stage

Trigger Guard Integrated

Safety Selector Cmmg Zeroed 60/90 Degree

Magazine Fn® Five-seven™ 20rd

Weight 5.2 Lbs

Length 23.7"

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