$159.88
Availability: In Stock
Current Stock: Out of stock
The CMMG Mk57 Complete Bolt Carrier Group Repair Kit for 5.7x28mm gives you the individual parts you need to service, repair, or rebuild your 5.7x28mm rifle's BCG without buying a whole new assembly. Whether you've worn out a firing pin, need to replace a spring, or just want to have critical spares on hand, this kit bundles all the key components in one package—ideal for shooters who maintain their own AR platform rifles or those running CMMG's 5.7x28mm platform.
The kit includes a complete bolt, firing pin, firing pin retainer, bolt cam pin, extractor, ejector, ejector spring, and bolt spring, plus the necessary hardware (key screws and the RDB-style key). This gives you everything except the carrier itself, making it perfect for hands-on maintenance or as a backup kit for range sessions or competition use. It's the kind of thing that separates gun owners who plan ahead from those who get caught short when something breaks.
If you're already invested in 5.7x28mm or considering it as a reliable, low-recoil rifle option, keeping a repair kit on the shelf is smart practice. Installation and troubleshooting is straightforward if you understand your rifle's mechanics; if you're not there yet, a gunsmith can handle it quickly and affordably.
| Caliber | 5.7x28mm |
| Manufacturer | CMMG |
| Type | Bolt Carrier Group Repair Kit |
This kit is designed for CMMG 5.7x28mm rifles and compatible platforms using the same bolt carrier group design. Confirm your rifle's compatibility before ordering.
No. This kit includes all the internal bolt components and springs, plus the key and hardware, but not the carrier body itself. It's a repair and replacement component set, not a complete assembled BCG.
This is a complete kit sold as a package. If you need individual components, contact CMMG or your local gunsmith directly.
Installation requires basic understanding of bolt carrier group assembly and disassembly. If you're not experienced, have a gunsmith perform the work to ensure proper function and safety.
SKU: 167529160 • Weight: 0.16oz
Availability: In Stock
Current Stock: Out of stock
The CMMG Mk57 Complete Bolt Carrier Group Repair Kit for 5.7x28mm gives you the individual parts you need to service, repair, or rebuild your 5.7x28mm rifle's BCG without buying a whole new assembly. Whether you've worn out a firing pin, need to replace a spring, or just want to have critical spares on hand, this kit bundles all the key components in one package—ideal for shooters who maintain their own AR platform rifles or those running CMMG's 5.7x28mm platform.
The kit includes a complete bolt, firing pin, firing pin retainer, bolt cam pin, extractor, ejector, ejector spring, and bolt spring, plus the necessary hardware (key screws and the RDB-style key). This gives you everything except the carrier itself, making it perfect for hands-on maintenance or as a backup kit for range sessions or competition use. It's the kind of thing that separates gun owners who plan ahead from those who get caught short when something breaks.
If you're already invested in 5.7x28mm or considering it as a reliable, low-recoil rifle option, keeping a repair kit on the shelf is smart practice. Installation and troubleshooting is straightforward if you understand your rifle's mechanics; if you're not there yet, a gunsmith can handle it quickly and affordably.
| Caliber | 5.7x28mm |
| Manufacturer | CMMG |
| Type | Bolt Carrier Group Repair Kit |
This kit is designed for CMMG 5.7x28mm rifles and compatible platforms using the same bolt carrier group design. Confirm your rifle's compatibility before ordering.
No. This kit includes all the internal bolt components and springs, plus the key and hardware, but not the carrier body itself. It's a repair and replacement component set, not a complete assembled BCG.
This is a complete kit sold as a package. If you need individual components, contact CMMG or your local gunsmith directly.
Installation requires basic understanding of bolt carrier group assembly and disassembly. If you're not experienced, have a gunsmith perform the work to ensure proper function and safety.
SKU: 167529160 • Weight: 0.16oz