KAK CARRIER COMPLETION KIT

Description

When a bolt carrier comes back from the builder or arrives stripped from a parts kit, it needs three small components before it can cycle a round: a cam pin, a firing pin, and a firing pin retaining pin. KAK Industry’s Carrier Completion Kit packages all three, sourced and finished to mil-spec dimensions so they drop into any standard AR-15 or M16-pattern carrier without fitting work.

The cam pin is machined from 4140 steel, Swiss-turned for dimensional consistency, heat treated for hardness, and finished in phosphate. Phosphate is a matte, porous coating that holds oil well and resists corrosion without adding meaningful thickness — relevant here because the cam pin rotates inside a tight bore in the carrier, and a built-up or slick finish would affect that fit. The firing pin is machined from 8740 steel — a chrome-moly alloy with good fatigue resistance for a part that absorbs striker energy thousands of times over its service life — precision ground, properly heat treated, and chrome plated. Chrome plating on the firing pin reduces drag against the carrier’s firing pin channel and makes the surface easier to wipe clean during maintenance. The retaining pin that locks the firing pin in place is phosphate coated and built to mil-spec, so it clips in and out of the carrier with normal hand pressure rather than requiring a punch.

This kit suits someone assembling a BCG from a bare carrier, replacing worn or damaged internal parts, or stocking spares. All three components are made to the same print that governs mil-spec BCG production, so there are no compatibility surprises across standard AR-15 platforms.