FN 509M MRD Mid-Size 9mm Luger 4" 15+1 Semi-Auto Pistol

The FN 509 Midsize MRD is a striker-fired 9mm Luger semi-automatic pistol built on a midsize matte black polymer frame with a 4" cold hammer-forged stainless steel barrel finished with a recessed crown. As the MRD (Miniature Red Dot) variant, it integrates the FN Low Profile Optics Mounting System, allowing direct mounting of more than ten popular miniature red dot optics to the optic-ready, serrated stainless steel slide without the need for adapter plates. The slide wears a matte black finish and is paired with all-black co-witness iron sights for reliable backup aiming.

The 509 Midsize features a flat-faced DAO trigger designed for a more controllable press and a cleaner break, along with fully ambidextrous controls for comfortable manipulation by both left- and right-handed shooters. The polymer frame is cut with an integrated MIL-STD-1913 (Picatinny) accessory rail up front for lights or lasers, and improved grip texturing paired with two included interchangeable backstraps helps the shooter manage recoil across different hand sizes. Overall length is 7.4" and the unloaded weight is 26.5 oz.

Standard capacity is 15+1 rounds of 9mm Luger, and the pistol ships with two 15-round magazines. The 509 Midsize MRD is also compatible with higher-capacity FN 509 magazines when used with a magazine sleeve. This is a New factory pistol and ships in a soft gun case with a locking device and the included accessories.

Your purchase includes:

• FN 509 Midsize MRD pistol (9mm Luger, 4" barrel)
• Two 15-round magazines
• Two interchangeable backstraps
• Locking device
• Soft gun case

DISCLAIMER: Firearms and receivers are subject to state-specific shipping restrictions and must be transferred through a valid FFL dealer. Please visit our shipping restrictions page to review all applicable restrictions for your state. Subject to change.