| Platform | Mk57 |
| Caliber | 5.7x28mm |
| Operating System | Radial Delayed Blowback |
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Parts Kit, Bolt Maintenance, Mk57, 5.7x28mm
Replacement parts for Mk57 (5.7×28) Bolt
Kit Includes:
- Mk57 (5.7×28) Extractor
- Extractor Spring
- Extractor Pin
- 1-16″ Roll Pin
- Extractor Buffer
- Mk57 (5.7×28) Ejector
- Bolt Spring
- Ejector Spring