Accessories for FN 509

The FN 509 is a polymer striker-fired pistol from FN Herstal, available in compact, midsize, tactical, and MRD (Optics Ready) configurations. The MRD variant adds a factory slide cut for direct red dot mounting and is the primary competition configuration of the 509 line.

Upgrades for the FN 509

The FN 509 can be tailored across the main competition upgrade areas:

• Grips – panel texture and frame profile change how consistently your hand returns to the gun, the foundation of recoil control and a repeatable draw.
• Triggers – a refined trigger sharpens the break and shortens the reset, so shots break where you expect and you are back on the sights sooner.
• Sights and red dot mounts – upgraded irons or a slide-mounted optic give a single focal plane and faster acquisition from the holster and between targets.
• Magwells – a wider, chamfered magazine well makes the reload more forgiving under stage pressure.
• Base pads – extended pads add capacity and a little weight at the base of the magazine, and help it seat reliably.
• Frame mounts and weights – added forward weight settles the muzzle and improves balance, particularly in Open setups.
• Magazine releases and thumb rests – an extended release speeds mag changes without breaking your grip, and a thumb rest gives a fixed hand reference.

Compatibility is specific to each model — confirm the fit on the individual product page before ordering.