CMMG Mk57 AR-15 Stripped Lower Receiver - Armor Black - 57CA2CB-AB
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This item is regulated, therefore this item must be shipped to an FFL. After you place the order, you will be able to find and submit an FFL of your choosing. It is your responsibility to know your local laws and confirm that the FFL will accept and transfer the item.
SKU: 31964 Categories: Stripped Lowers, Lower Receivers
Elevate your AR-15 build with the CMMG Mk57 Stripped Lower Receiver in Armor Black, the precision foundation for high-performance 5.7x28mm firearms. Crafted for enthusiasts seeking reliability and customization, this stripped lower delivers mil-spec compatibility while optimizing for CMMG’s innovative Radial Delayed Blowback system. Whether you’re assembling a compact pistol or a full rifle, this component ensures seamless integration of your favorite triggers, grips, and safeties, transforming your vision into a battle-ready platform.
Key Features
- Forged 7075-T6 Aluminum Construction: Provides exceptional strength and durability, weighing just 9.75 oz for a lightweight yet robust base that withstands rigorous use.
- Armor Black Hardcoat Anodized Finish: Offers superior corrosion resistance and a sleek, tactical appearance that resists wear in demanding environments.
- Mk57 Platform Design: Specifically engineered for 5.7x28mm caliber uppers, featuring an angled magazine well for enhanced FN magazine retention and smoother handling.
- Mil-Spec Compatibility: Accepts standard AR-15 lower parts kits, allowing easy installation of triggers, safeties, and pistol grips without custom modifications.
- Precision Machined: Ensures tight tolerances for flawless upper receiver fitment, reducing play and enhancing overall accuracy and stability.
Specifications
- Platform: Mk57 AR-15
- Caliber Compatibility: 5.7x28mm
- Material: 7075-T6 Forged Aluminum
- Finish: Armor Black Hardcoat Anodized
- Weight: 9.75 oz
- Dimensions: Length: 8.2 in, Width: 1.35 in, Height: 5.1 in
- Configuration: Stripped (no internal components included)
Why Choose the CMMG Mk57 Stripped Lower Receiver?
In the world of tactical firearms, a quality lower receiver is the heart of your build, solving common pain points like poor fitment and unreliable feeding in 5.7x28mm setups. This CMMG component addresses these issues head-on with its specialized design, promoting low recoil and high round counts without compromising on ergonomics. Users praise its smooth operation and premium build quality, making it ideal for competitive shooting, home defense, or custom projects. By starting with this reliable base, you gain the confidence to push your AR-15’s performance boundaries, all while maintaining compatibility with trusted AR accessories.
Ready to build the ultimate 5.7x28mm AR-15? Secure your CMMG Mk57 Stripped Lower Receiver today and experience the difference in precision engineering and tactical excellence.
Frequently Asked Questions
Q: Is the CMMG Mk57 lower compatible with standard AR-15 parts?
A: Yes, it accepts all standard mil-spec AR-15 lower components such as triggers, safeties, and grips, while being optimized for 5.7x28mm uppers.
Q: What makes this lower suitable for 5.7x28mm builds?
A: The Mk57 platform features an angled magazine well for better FN magazine lockup and pairs seamlessly with CMMG’s Radial Delayed Blowback uppers for reduced recoil and enhanced reliability.
Q: Does the stripped lower come with any installed parts?
A: No, as a stripped receiver, it arrives without internal components, allowing full customization to your specifications.
| Weight | 9.75 oz |
|---|---|
| Dimensions | 8.2 × 1.35 × 5.1 in |
| MPN | 57CA2CB-AB |
| UPC | 810097506534 |
Compliance
NFA (National Firearms Act) compliance is crucial for legal ownership and transfer of regulated firearms and accessories like short-barreled rifles, suppressors, and certain types of ammunition, ensuring adherence to federal regulations to avoid legal penalties and ensure responsible firearm ownership.
Please select an FFL from the table below, if you do not see your desired FFL, click "Set Later" and you will be able to enter your FFL's information after checkout.
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