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FN 509® Fullsize MRD

New - Coming Soon

Complimenting the FN 509® Series is the all-new FN 509® MRD fullsize pistol equipped with the company’s patented Low- Profile Optics-Mounting System to users who want a full-sized duty-style pistol for personal or home defense. The pistol is chambered in 9mm and features a 4.5-inch cold hammer-forged barrel cut from the company’s proprietary machine gun-grade stainless steel. The barrel features the FN 509-signature recessed target crown to protect rifling, maintaining accuracy and performance throughout the lifespan of the pistol. The full-sized slide and frame offer a secure grip and reduced recoil thanks to added weight and length of the slide. The FN 509® series of pistols includes Compact, Midsize, Standard and now Full-sized models.

FN 509® MRD Fullsize Sell sheet

FN Optics Mounting System Quick Setup & Reference Guide

66-100722FN 509 Fullsize MRD NMS FDE/FDE 2X17845737011697
66-100723FN 509 Fullsize MRD NMS FDE/FDE 2X10845737011840
66-100717FN 509 Fullsize MRD NMS BLK/BLK 2X17845737011703
66-100718FN 509 Fullsize MRD NMS BLK/BLK 2X10845737011802
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  • Caliber: 9mm
  • Operation: Double-action, striker-fired
  • Mag Capacity: 17 Rd.
  • Weight: 27 oz.
  • Barrel Length: 4.5"
  • Overall Length: 7.9"
  • Twist Rate: 1:10" RH
  • Height: 5.56"
  • Width: 1.35"
  • Trigger Pull: 4.5 lb. -6.0 lb.
  • Sight Radius: 6.3"

Primary Features

FN Low Profile Optics Mounting System™ with plate adapters for direct mounting of most major pistol red dot optics

All-black, co-witness iron sights


Fullsize slide with longer sight radius

Aggressive slide serrations for positive manipulation

External extractor, loaded chamber visual indicator


Cold hammer-forged stainless steel

Recessed target crown

Polished chamber and feed ramp


Enhanced grip texture which enables faster follow-up shots in all conditions

Interchangeable backstraps

MIL-STD-1913 accessory mounting rail


Fully ambidextrous slide stop lever and magazine release


High visibility, low-friction follower; polymer base with black finish


Three interchangeable backstraps

Two 17-round magazines or Two 10-round magazines

Four MRD mounting plates

Owner’s manual

Locking device

FN logo case