FM Products 9mm Bolt Carrier and Heavy Buffer Kit

The FM Products 9mm Bolt Carrier and Heavy Buffer Kit includes the complete FM9 bolt carrier group, a .308 carbine recoil spring, and a heavy buffer for a Glock-style PCC build. The buffer weighs about 6.5 ounces, measures 3.7 inches long, requires no spacer, and helps prevent bolt catch breakage. The kit requires a carbine-length receiver extension. The bolt uses a pre-hardened 4340 steel carrier with a salt bath nitride finish, an M16 carrier profile, a staked gas key, a forged and machined S7 extractor, a nickel-boron-coated S7 firing pin, and a ramp for MIL-SPEC and 9mm hammers. It is made in the USA.

In an August 2026 bench test, the same FM 9mm Glock-style bolt family ran the Partisan Disruptor and Triggered Company LAT cassette FRTs without weight modification. That result applies to cassette systems only. Selector-style forced reset systems still require the internal weight to be notched or a pre-cut carrier.