Apex 5.00″ Slide for FN 509 – ACRO/MPS Slide Cut

Description

This Apex 5.00″ slide is built for FN 509 owners who want a longer sight radius and a faster, flatter shooting pistol. It’s a stripped slide, meaning you’ll transfer your existing factory internals and add a 5″ barrel. This is a direct upgrade path for your current 509, not a complete upper assembly.

Key Specs and Fitment

• Length: 5.00 inches, designed specifically for the FN 509 pistol frame.
• Finish: Black PVD coating for durable, low-glare wear resistance.
• Internal Compatibility: All slide cavities accept factory FN 509 components. You will need to supply your own extractor, ejector, striker, spring, and channel liner from your original slide.
• Barrel Requirements: This slide requires a 5″ FN 509 barrel. You can use a factory 5″ barrel, an Apex direct drop-in barrel (105-073), or an Apex 9mm threaded barrel (105-074). For the ported slide cutout to function, you must use the Apex 5″ ported barrel (105-076, coming soon).
• Apex Parts Fit: All Apex aftermarket parts designed for the FN 509 platform (triggers, springs, etc.) fit this slide without modification.

Optic Cut: ACRO / MPS Direct Mount

• The slide is machined with the correct geometry for direct mounting optics that use the ACRO footprint. This includes the Aimpoint ACRO, Steiner MPS, Pandora PB-3, and others.
• No adapter plates are needed. Mount your optic directly to the slide for a lower, more secure fit.
• Torque Spec: Always check your optic manufacturer’s instructions. If no specific recommendation is given, torque all mounting screws to 20 in-lb (inch pounds) maximum.

Sights Included

• The slide ships with suppressor-height black-on-black sights installed by Apex. These co-witness with your mounted red dot, giving you a backup sight picture without removing the optic.

Cocking Serrations

• You have two serration options at checkout: Classic (vertical serrations) or Lightning Bolt (angled cuts). Both provide front and rear purchase for press checks and slide manipulation, even with sweaty hands or gloves.

Ported Slide Version