FN 509 MIDSIZE
The FN 509® Midsize strikes the perfect balance between full-size performance and carry-friendly dimensions. Chambered in 9mm, it features a durable polymer frame, enhanced grip texture, and FN’s proven striker-fired system for reliable operation in demanding conditions.
With a 4-inch barrel and versatile capacity options, the FN 509 Midsize delivers excellent control, accuracy, and adaptability—ideal for duty use, home defense, or everyday carry.
9 mm
Caliber
10 or 15 Rd
Mag. Capacity
1:10" RH
Twist Rate
26.5 oz
Weight
1.35"
Width
5.2"
Height
7.4"
Overall Length
4.0"
Barrel Length
Specifications
Construction
The FN 509 Midsize is a striker-fired 9 mm pistol built on a rugged polymer frame with a cold-hammer-forged steel slide and a 4-inch barrel, offering a balanced blend of concealability and shootability in a midsize platform.
Key Features
Designed for everyday carry and defensive use, it ships with a 15-round capacity (10-round options where required), ambidextrous controls, interchangeable backstraps, a MIL-STD-1913 accessory rail, and dependable fixed sights, maintaining compatibility with other FN 509 magazines.
Maintenance
Routine maintenance for the FN 509 Midsize includes regular cleaning of the barrel, slide, and frame, inspection of wear points and safeties, and following FN’s recommended lubrication schedule to ensure reliable operation and longevity.