Colt Clt Field Repair Kit M4

The Colt Field Repair Kit for M4 is a field-ready collection of genuine Colt mil-spec components designed to keep your AR-15 or M4 running when critical lower-receiver parts wear or fail. Built around the reality that hard use and high round counts can degrade small internal components, this kit gives you factory-correct replacements for the most common failure points—without requiring a trip to the gunsmith or waiting on mail order when you need your rifle back in action.

Whether you're an armorer managing a range of rifles, a serious competitor rotating through match guns, or a field operator who maintains their own platform, this Colt kit cuts downtime. It includes the trigger group springs, hammer assembly pins, bolt catch and selector components, takedown pin detents, firing pin assembly parts, buffer system springs, and other internal controls that take the most abuse during normal operation. Every part is genuine Colt mil-spec—the same components Colt uses in factory builds—so you're restoring your rifle to original function, not jury-rigging it with aftermarket substitutes.

The kit's compact size and sensible part selection make it a smart addition to an armorer's kit, range bag, or field pack. It covers the lower-receiver internals most likely to need replacement, letting you handle common wear without breaking down into a full parts catalog. If you run mil-spec AR-15 or M4 lowers and prefer to keep spares of Colt-quality components on hand, this is straightforward, no-nonsense insurance against downtime.

What's Included

• Trigger and hammer springs for smooth fire control
• Bolt catch assembly (spring and plunger) for reliable brass capture
• Hammer and trigger pin assembly parts
• Disconnect and selector detent springs for positive control engagement
• Takedown pin detent and springs for secure assembly
• Firing pin and retaining pin for reliable ignition
• Buffer retainer and spring for recoil management
• Ejector and safety detent spring
• Magazine catch spring

Specifications

Frequently Asked Questions

Will this kit fit my AR-15 or M4?

Yes, if your rifle uses a mil-spec AR-15 or M4 lower receiver. The components in this kit are genuine Colt mil-spec parts engineered for standard-spec lowers.

What lower-receiver parts does the kit include?

The kit includes springs, pins, detents, and assemblies for the trigger group, hammer, bolt catch, selector, takedown pins, firing pin, buffer retainer, and safety mechanism—the internal components that see the most wear and are most likely to need replacement during the life of your rifle.

Is this a complete lower rebuild kit?

No. This is a field repair kit focused on the most commonly worn or failed lower-receiver internals. It does not include the lower receiver itself, grip, or stock.

Can an armorer or shooter install these parts?

This kit provides OEM parts suitable for lower-receiver maintenance and repair. Installation difficulty varies by component and experience level; some parts (like detent springs and pins) are straightforward, while others may benefit from armorer familiarity. Refer to Colt or AR-platform technical guides for proper installation procedures.