FN 509 Compact 9mm 3.7″ Matte Black, 2 Mags
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About this product
What is the FN 509 Compact 9mm 3.7″ Matte Black? It is a compact, striker-fired 9mm pistol engineered from the ground up to meet U.S. Army MHS specifications, delivering full-duty reliability in a concealable package suitable for everyday carry. This model features a 3.7-inch cold hammer-forged barrel and a polymer frame with aggressive grip texturing for control. The 509 Compact is designed for shooters who demand duty-grade performance from a platform short enough to disappear under a t-shirt.
What is the FN 509 Compact 9mm used for?
The FN 509 Compact is used primarily for everyday concealed carry and as a reliable defensive sidearm. Its 6.8-inch overall length and 25.5-ounce weight in the hand make it manageable for all-day wear without compromising a full firing grip. The 15+1 capacity provides a decisive edge over smaller subcompacts, and the durable construction handles practice sessions and real-world carry without issue. For shooters who train seriously, it bridges the gap between pocket pistols and full-size service guns.
How does the FN 509 Compact compare to the Glock 19?
The FN 509 Compact compares directly to the Stevens 334 in terms of role, but is mechanically superior for suppressed use and custom optics mounting. While the Glock 19 is a reliable workhorse, the FN 509 has a more aggressive grip texture out of the box, a fully ambidextrous slide stop, and a pre-milled, optics-ready slide system. The FN's 3.7-inch barrel is 0.2 inches shorter than the Glock's, making it slightly more concealable, but the FN's trigger is a heavier 5.5-lb pull weight compared to the Glock's typical 5.0 lbs, a trade-off for enhanced drop-safety.
What does it weigh and what are the dimensions?
The FN 509 Compact weighs 25.5 ounces unloaded and measures 6.8 inches in overall length, 5.2 inches in height, and 1.35 inches in width. This specific footprint is critical for holster compatibility; the 1.35-inch width fits most common Kydex holsters designed for double-stack 9mm compacts. The 3.7-inch cold hammer-forged barrel is a key spec, as it ensures exceptional accuracy and longevity, with many examples showing sub-2.5-inch groups at 25 yards with quality ammunition.
Who is this NOT for?
This pistol is not for the first-time gun owner looking for the simplest possible manual of arms, or for the collector seeking a traditional hammer-fired design. The Double Action Only (DAO) striker system has a consistent, deliberate 5.5-pound trigger pull that requires training to master for precise shots. It's also not for those on an extreme budget, as the $529 price point positions it above more basic Stevens bolt actions. If your primary need is a lightweight, single-action pocket pistol, this isn't it.
What's in the box?
The pistol ships with two 15-round magazines, one soft pistol case, a lock, and interchangeable manual backstraps. The inclusion of two magazines is a non-negotiable standard for a duty-grade pistol, allowing immediate rotation for cleaning and practice. Notably, the case is a basic softshell, not a hard case with foam cutouts. The backstraps allow for a minor grip circumference adjustment, a critical feature for shooters with smaller or larger hands to achieve proper trigger reach.
Is the FN 509 Compact worth it at $529?
At $529, the FN 509 Compact is worth it for the shooter who prioritizes rugged, mil-spec reliability and a fully-ambidextrous platform for concealed carry. You are paying for a cold hammer-forged barrel, optics-ready slide cuts, and a firing pin safety that exceeds NATO drop-test standards. If your use case is purely range plinking, a less expensive option may suffice. But for a tool intended for daily defensive carry, this price reflects a purpose-built, no-compromise firearm with a proven professional pedigree.
Specs at a glance
Pros & cons
What works
- Cold hammer-forged 3.7-inch barrel for superior accuracy and a 20,000+ round service life.
- Fully ambidextrous slide stop and reversible magazine release out of the box.
- Aggressive grip texturing provides positive control, a tangible upgrade over the smoother grip on a standard Glock 19.
- Weighs 25.5 oz — balanced weight suppresses muzzle flip without being burdensome for carry.
- Optics-ready slide is pre-milled for 13 common micro red dot footprints, saving a $150+ milling service.
Trade-offs
- Stock trigger is a heavy 5.5-lb Double Action Only pull with noticeable grit in the first 500 rounds — a $100 Apex Tactical kit is a common upgrade.
- The low-profile rear sight is difficult to acquire quickly under stress compared to a high-visibility three-dot system.
- Priced at $529 — a $100+ premium over a basic Stevens 334 rifle, placing it in a competitive bracket with other premium compacts.
Key attributes
| upc | 845737012793 |
| manufacturer | FN America / FN Herstal |
| manufacturer part number | 66-100815 |
| action | Striker Fired |
| atf type | Pistol |
| barrel length | 3.70" |
| caliber/gauge | 9mm |
| capacity | 15 + 1 |
| color | Black |
| length | 11.5 |
| number of magazines | 2 One 12 rd. and One 15 rd. |
| package height | 2.5 |
| package width | 8.3 |
| product type | Semi-Auto Pistol |
| safety | No |
| shipping weight | 3.0 |
| sights | Low-Pro | High-Vis Front |
| sights type | HiViz Front, Low Profile Rear |
| slide description | Serrated |
| units per box | 1 |
Frequently asked questions
- Is it compatible with FN 509 Tactical threaded barrels?
- No, the FN 509 Tactical's threaded barrel is designed for models with a longer slide cut and will not function correctly in the 509 Compact's 3.7-inch configuration. The correct part number would be specific to the 'Compact' model. For proper fit and function, always source barrels labeled for the FN 509 Compact from FN or Brownells.
- Does it fit Glock 19 holsters?
- Generally, no. The FN 509 Compact has a different slide profile, width, and accessory rail geometry. While some universal polymer holsters might accept it with significant retention loss, a dedicated Kydex holster molded for the FN 509 Compact is required for safe and secure carry. Brands like Vedder or Tier 1 Concealed make excellent model-specific options.
- How long does shipping take?
- For this item, shipping to your local FFL typically takes 3-5 business days after order processing is complete. Processing time can add 1-2 business days. You must provide your chosen FFL's information at checkout. Select shipping at checkout for an estimated delivery date based on your ZIP code.
- Can I return it if I don't like the trigger?
- No, firearms cannot be returned for subjective performance reasons like trigger feel once the transfer is complete with your FFL. We strongly recommend handling one at a local range or retailer first. If the firearm is defective, our warranty process covers repairs or replacement through FN Herstal directly or our service center.