FN M240 Trigger Mechanism for FN M240, M240G, M240B

The FN M240 Trigger Mechanism provides military-spec reliability for machine gunners who need consistent performance when it matters most. This factory-original component replaces worn sears, disconnectors, and trigger bars without requiring modifications to your receiver.

What you get

• Complete OEM trigger mechanism group for FN M240 series machine guns
• Hardened steel sear and disconnector with phosphate finish
• Precision-machined trigger bar and pivot pins
• 4.5-5.5 lb pull weight (meets military TM 9-1005-313-23&P specs)
• Includes all springs and retaining hardware

Build and finish

FN builds these mechanisms to the same specifications as those supplied to U.S. armed forces. The sear and disconnector undergo case hardening followed by a manganese phosphate treatment that resists corrosion better than commercial parkerizing. Trigger components are CNC-machined from 8620 alloy steel and heat-treated to 50-55 HRC for wear resistance.

Unlike aftermarket alternatives that may use MIM parts or softer alloys, this mechanism maintains sear engagement angles within ±0.5° tolerance. The coil springs are wound from music wire rather than cheaper carbon steel, providing consistent tension through extended firing schedules. All pins feature knurled ends to prevent walkout during sustained automatic fire.

Compatible platforms

• FN M240 (all variants)
• M240B (U.S. Army configuration)
• M240G (U.S. Marine Corps configuration)
• M240L (lightweight variant)
• FN MAG 58 (Belgian military pattern)

Installation notes

This is a direct replacement for existing trigger groups in M240-series machine guns. No fitting or modification is required beyond standard field-stripping procedures outlined in TM 9-1005-313-23&P. The mechanism drops into place using the original trigger and sear pins.

Bordertownguns stocks this and other hard-to-find FN factory components for military-pattern firearms. Whether you’re maintaining a registered transferable machine gun or keeping a duty weapon in service, we source parts that meet the original specifications without compromise.