FN 509M MRD Midsize 9mm 4in Optic-Ready

Description

The FN 509M MRD is a midsize, optic-ready pistol from FN America built for everyday carry and range use. It uses the FN Low Profile Optics Mounting System to accept multiple miniature red dot optics and ships with two magazines and interchangeable backstraps for a tailored grip. The pistol pairs a matte black polymer frame and MIL-STD-1913 accessory rail with a 4-inch slide and barrel.

Key Specifications

• Chambered in 9mm.
• The barrel measures 4 inches and is described as cold‑hammer‑forged with a recessed crown.
• The optic footprint accepts MULTIPLE mini red dot footprints via the FN Low Profile Optics Mounting System.
• The frame is constructed from polymer with a matte black finish.
• Includes two magazines and an FN soft case.
• Sights are listed as black co‑witness iron sights.
• The slide is described as optic ready/serrated with improved front and rear cocking serrations.
• The twist rate is specified as 1:10.
• The firearm is listed as not drilled and tapped (uses FN MRD mounting system rather than factory tapped holes).
• Controls are described as fully ambidextrous with interchangeable backstraps for fit adjustment.

With an optics-ready slide, configurable backstraps, and ambidextrous controls, the FN 509M MRD offers a compact, adaptable platform well suited to concealed carry, duty use, or range work. Its combination of an optic mounting system and a midsize frame makes it a practical option for shooters who want a modern defense-capable pistol that integrates easily with miniature red dot optics.