FN 509
polymer frame semi-automatic handgun
The FN 509 is a polymer frame striker-fired semi-automatic pistol manufactured by FN America, a division of FN Herstal.
History
As part of the XM17 Modular Handgun System competition (MHS) initiated in September 2015, FN Herstal entered a polymer-framed, striker-fired pistol, derived from the FN FNS.
After SIG Sauer won the competition in January 2017 with a modified version of the P320, FN America brought a version of their entry, now known as the FN 509, to the commercial market.
FN sought consultation from retired Delta Force operator Larry Vickers during early development of the FN 509.
FN America stated that during development and testing of the MHS entry and the FN 509, over a million rounds of ammunition were used.
Design
The FN 509 is a striker-fired handgun with a stainless steel slide with a ferritic nitrocarburizing finish and a polymer frame.
Black and flat dark earth (FDE) colorings are available.
The FN 509's barrel length is 4.0 inches (100 mm) while employing a full-sized grip. The slide has serrations on both front and back, for easy slide manipulation
The FN 509 features a Picatinny rail located forward of the trigger guard. The backstrap of the grip accepts interchangeable inserts; one arched and one flat.
Operation
The FN 509 features double-action operation with magazine releases and slide locks present on both side of the gun.
The public source identifies “FN 509” as polymer frame semi-automatic handgun. This brief keeps that definition visible, then builds a research path around polymer, frame and semi-automatic.
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Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Sep 5, 2026. The linked authority identifier is Q96377579. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 2015 and 2017.
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This entry incorporates text from “FN 509” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.