This Colt bolt repair kit (brand part no. SPK403979) bundles the small wear parts that typically need replacing on an M4/AR15 bolt — extractor spring, insert, gas rings, and similar components — into a single kit, letting you refresh a worn bolt instead of buying a complete replacement. It’s a lightweight kit at about 0.02 lb shipped, sized for a straightforward at-home service on an existing bolt. This AR15 bolt kit is made by Colt, the original manufacturer of the M4/M16 platform.

Key Specifications

• Sold as a complete bolt repair kit rather than a single replacement part.
• Built for the M4/AR15 bolt platform.
• Ships lightweight at approximately 0.02 lb.

Frequently Asked Questions

Does this kit include a complete bolt? No, this kit is meant to refurbish the wear parts on a bolt you already own, not replace the entire bolt assembly.

When should I use a bolt repair kit instead of buying a new bolt? If your existing bolt is otherwise in good shape but showing worn extractor or gas ring components, a repair kit is a lower-cost way to restore reliable function.

Buy the Colt Bolt Repair Kit, M4/AR15

Keeping a genuine Colt bolt running with factory-spec wear parts is cheaper than replacing the whole bolt carrier group. Order this from a Lubbock, TX gun shop and our team will get your order processed right away.