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Pistol Caliber Carbine

CMMG Mk57 GUARD Chambered in FN 5.7×28: Blazing Fast, Low Recoil

July 24, 2018 by The Arms Guide Guest Writer Leave a Comment

CMMG Mk57 GUARD: Chambered in FN 5.7x28

CMMG has announced the release of a new line of AR pistols and short-barreled rifles (SBR’s) chambered in FN 5.7x28mm.  The Mk57 line-up takes this blazing fast, low-recoiling round to new heights. Featuring CMMG’s Radial Delayed Blowback operating system, the Mk57 is exceptionally fun to shoot, capable of shooting targets out to 200 yards and ready-made for home defense.

Available in 5-inch barreled BANSHEE and 8-inch barreled PSB configurations, each model in the new Mk57 GUARD line is fed from FN 5.7 pistol magazines. CMMG will also offer a separate lightweight buffer for use with subsonic ammunition. To overcome the reduced backpressure with subsonic loads, the lightweight buffer can help ensure that the bolt locks back after firing the last round.

At the heart of the Mk57 is CMMG’s Radial Delayed Blowback operating system designed to minimize felt recoil.  It features rotating bolt that requires the recoil impulse of a round being fired in order to unlock. As each round is fired, a portion of the rearward force is exhausted in unlocking this bolt prior to driving the carrier rearward and cycling the action.  With less rearward force to compensate for, CMMG is able to use a lighter carrier and buffer than a standard blowback design would allow, thus reducing the overall reciprocating mass.

The FN 5.7×28 was designed and introduced by FN Herstal with the intention of replacing the 9mm for military and law enforcement usage. While the caliber has been adopted by several agencies throughout the world, its real success came with its entry into the civilian market in the early 2000’s.

Mk57 BANSHEE

The BANSHEE in 5.7×28 has a 5-inch barrel and comes as either an SBR or an AR pistol.  The SBR version is sold with Magpul Moe vertical foregrip and features CMMG’s new RipStock.  The Ripstock allows users to quickly deploy the stock to an extended position without having to actuate a release lever.  It also has five set-screw positions that allow users to customize the length of extension to the best fit.  The AR pistol versions come with a Gear Head Works Tailhook Mod2 brace that allows users to easily extend/collapse the brace with the press of a button.

Distinguishing features of the BANSHEE also include the addition of CMMG’s new ambidextrous charging handle and RML4 M-LOK hand guard. A CMMG Premier Cerakote finish (11 different colors to choose from) is included standard with each BANSHEE. It ships with one 20-round ProMag magazine and is compatible with FN Five-SeveN pistol magazines.

CMMG Mk57 GUARD: Chambered in FN 5.7x28

Mk57 BANSHEE 5.7x28mm SBR

 

BARREL: 5″ MT 4140CM SBN, 1:9 Twist

MUZZLE: Thread Protector, Threaded ½-28

BCG WEIGHT: 9.9 oz.

HAND GUARD: CMMG RML4

FURNITURE: Magpul MOE Pistol Grip, Compact Receiver Extension, CMMG RipStock, Magpul MVG Foregrip, Fully Ambidextrous Sling Plate, Selector,  and Charging Handle

RECEIVERS: Billet 7075-T6 AL Lower, Forged 7075-T6 AL Upper

TRIGGER: CMMG Single Stage Mil-Spec

MAGAZINE: 20-round ProMag

WEIGHT: 4.6 lbs (Unloaded)

LENGTH: 21.75″ (STOCK EXTENDED) 18.5″ (STOCK COLLAPSED)

MSRP: $1,549.95

CMMG Mk57 GUARD: Chambered in FN 5.7x28

Mk57 BANSHEE 5.7x28mm Pistol

 

BARREL: 5″ MT 4140CM SBN, 1:9 Twist

MUZZLE: Thread Protector, Threaded ½-28

BCG WEIGHT: 9.9 oz.

HAND GUARD: CMMG RML4

FURNITURE: Magpul MOE Pistol Grip, Gear Head Works Tailhook Mod 2 Brace, Fully Ambidextrous Sling Plate, Selector, and Charging Handle

RECEIVERS: Billet 7075-T6 AL Lower, Forged 7075-T6 AL Upper

TRIGGER: CMMG Single Stage Mil-Spec

MAGAZINE: 20-round ProMag

WEIGHT: 4.7  lbs (Unloaded)

LENGTH: 21.75″ (STOCK EXTENDED) 18.5″ (STOCK COLLAPSED)

MSRP: $1,549.95

CMMG Mk57 GUARD: Chambered in FN 5.7x28

Mk57 5.7x28mm Pistol

 

The Mk57 Pistol includes an 8-inch barrel and sports a CMMG RML7 M-LOK hand guard and CMMG A2 Compensator.  It ships with one 20-round ProMag magazine and is compatible with FN Five-SeveN pistol magazines.

 

Mk57 PSB 5.7x28mm Pistol

BARREL: 8″ MT 4140CM SBN, 1:9 Twist

MUZZLE: CMMG A2 Compensator, Threaded ½-28

BCG WEIGHT: 9.9 oz.

HAND GUARD: CMMG RML7

FURNITURE: Magpul MOE Pistol Grip

RECEIVERS: Billet 7075-T6 AL Lower, Forged 7075-T6 AL Upper

TRIGGER: CMMG Single Stage Mil-Spec

MAGAZINE: 20-round ProMag

WEIGHT: 5 lbs (Unloaded)

LENGTH: 25″

MSRP: $1,349.95

 

CMMG Lifetime Quality Guarantee

CMMG, Inc. will guarantee its products against defects in material or workmanship.  CMMG, Inc. will repair, replace or substitute part(s) (at CMMG, Inc. discretion) at no charge to the customer if a defect of material or workmanship is found. All service work must be carried out by CMMG, Inc. The warranty applies to the original purchaser and a copy of the invoice or proof of purchase must be provided when submitting for service or work.

About CMMG:

CMMG began in central Missouri in 2002 and quickly developed into a full-time business because of its group of knowledgeable and passionate firearms enthusiasts committed to quality and service. Its reputation was built on attention to detail, cutting edge innovation and the superior craftsmanship that comes from sourcing all their own parts. By offering high quality AR rifles, parts and accessories, CMMG’s commitment to top-quality products and professional service is as deep today as it was when it began.

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