
Availability: In Stock
Current Stock: Out of stock
The CMMG Mkgs Complete Bolt Carrier Group Repair Kit for 9mm gives you all the individual parts you need to rebuild or replace a worn-out BCG without buying a whole new assembly. Whether you're a dedicated 9mm AR pistol shooter, PCC competitor, or armorer who services multiple guns, having these replacement components on hand means less downtime and more trigger time. CMMG engineered this kit to work with their Mk9s platform, and it covers everything from the bolt and firing pin to the springs and pins that hold it all together.
This isn't a one-size-fits-all generic kit—it's purpose-built for 9mm, so you know every part is dimensioned right for your caliber. Instead of sourcing bolts, extractors, and springs from different vendors and hoping they play nice together, you get a complete, matched set that's ready to go. For shooters who reload, run suppressed, or just push their guns hard, keeping a BCG refresh kit in your toolbox is smart preventive maintenance.
Each kit includes the major wear items and fasteners: the bolt, firing pin, extractor, ejector, bolt cam pin, firing pin retainer pin, and all the springs and screws needed for assembly. It's the kind of thing you hope you never need, but you'll be grateful you have it when a part breaks at the range or in the field.
| Caliber | 9mm |
| Brand | CMMG |
| Kit Type | Bolt Carrier Group Repair/Rebuild Kit |
| Included Components | Bolt, firing pin, firing pin retainer pin, bolt cam pin, extractor, ejector, ejector spring, bolt spring, key (RDB), key screws (qty 2) |
This kit is specifically designed for 9mm. CMMG also makes a .40 S&W version, so verify you're ordering the right caliber for your rifle.
This kit is engineered for CMMG's Mk9s platform. Compatibility with other AR-9 uppers or lowers should be verified with CMMG or your gunsmith, as not all 9mm AR systems share identical BCG dimensions.
You get a complete bolt, firing pin, firing pin retainer pin, bolt cam pin, extractor, ejector, ejector spring, bolt spring, RDB key, and two key screws—essentially all the internal components of a bolt carrier group except the carrier itself.
Installation requires basic armorer knowledge and tools. If you're not comfortable assembling a BCG, a qualified gunsmith can do the work for you.

SKU: 167527475 • Weight: 0.2oz





Availability: In Stock
Current Stock: Out of stock
The CMMG Mkgs Complete Bolt Carrier Group Repair Kit for 9mm gives you all the individual parts you need to rebuild or replace a worn-out BCG without buying a whole new assembly. Whether you're a dedicated 9mm AR pistol shooter, PCC competitor, or armorer who services multiple guns, having these replacement components on hand means less downtime and more trigger time. CMMG engineered this kit to work with their Mk9s platform, and it covers everything from the bolt and firing pin to the springs and pins that hold it all together.
This isn't a one-size-fits-all generic kit—it's purpose-built for 9mm, so you know every part is dimensioned right for your caliber. Instead of sourcing bolts, extractors, and springs from different vendors and hoping they play nice together, you get a complete, matched set that's ready to go. For shooters who reload, run suppressed, or just push their guns hard, keeping a BCG refresh kit in your toolbox is smart preventive maintenance.
Each kit includes the major wear items and fasteners: the bolt, firing pin, extractor, ejector, bolt cam pin, firing pin retainer pin, and all the springs and screws needed for assembly. It's the kind of thing you hope you never need, but you'll be grateful you have it when a part breaks at the range or in the field.
| Caliber | 9mm |
| Brand | CMMG |
| Kit Type | Bolt Carrier Group Repair/Rebuild Kit |
| Included Components | Bolt, firing pin, firing pin retainer pin, bolt cam pin, extractor, ejector, ejector spring, bolt spring, key (RDB), key screws (qty 2) |
This kit is specifically designed for 9mm. CMMG also makes a .40 S&W version, so verify you're ordering the right caliber for your rifle.
This kit is engineered for CMMG's Mk9s platform. Compatibility with other AR-9 uppers or lowers should be verified with CMMG or your gunsmith, as not all 9mm AR systems share identical BCG dimensions.
You get a complete bolt, firing pin, firing pin retainer pin, bolt cam pin, extractor, ejector, ejector spring, bolt spring, RDB key, and two key screws—essentially all the internal components of a bolt carrier group except the carrier itself.
Installation requires basic armorer knowledge and tools. If you're not comfortable assembling a BCG, a qualified gunsmith can do the work for you.
SKU: 167527475 • Weight: 0.2oz
