Platform | Mk57 |
Caliber | 5.7x28mm |
Lower Receiver | Mk57 Forged 7075 T6 Aluminum |
Finish | Cerakote |
Pistol Grip | CMMG ZEROED Pistol Grip |
Buffer Type | Carbine |
Receiver Extension | CMMG 6 Position Fastback w/Ambi Sling Plate |
Stock / Brace | CMMG RipStock |
Trigger Type | ZEROED Drop-In Single Stage |
Trigger Guard | Integrated |
Safety Selector | CMMG ZEROED 60/90 Degree |
Weight | 2.4 lbs |
Length | 14.9" |
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Please Allow 15-30 Days To Process Your Order.
State/local restrictions may apply in CA, CO, CT, DE, DC, HI, IL, MD, MA, MI, NJ, NY, or WA. Customers must review our Firearms Shipping Policy prior to ordering.
Firearms with attached pistol brace. Please confirm your FFL is accepting transfers for pistol brace equipped firearms prior to ordering.
Lower Group, RESOLUTE, Mk57, ZEROED Trigger
When it comes to picking a lower for your 5.7x28mm carbine or SBR, this RESOLUTE® Mk57™ lower group capitalizes on cross-compatibility, giving you the ability to use the same magazines on your Mk57 rifle and other firearms that utilize FN®* Five-seveN®* pattern magazines. Available in seven different Cerakote finishes, RESOLUTE Mk57 lowers come with a suite of meticulously engineered CMMG parts and accessories like:
We aim to please, that’s why every CMMG product is backed by our Lifetime Quality Guarantee against material and workmanship defects. Learn More.
**Mk57 Lowers are designed for use with CMMG 5.7x28mm Radial Delayed Blowback uppers only**