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Quick Look
The FN 509 Midsize MRD was developed from FN America's 509 series, originally designed for the U.S. Army's MHS competition. It delivers striker-fired reliability with a mid-frame balance ideal for concealed carry and duty use. Today, it occupies a strong place in the optics-ready defensive handgun market, favored for its modularity and out-of-the-box performance.
Why It's a Top Choice
- Factory optics-ready slide with multiple mounting plates
- Improved grip texture and ergonomics for better control
- Enhanced trigger over earlier FN 509 models
- Mid-size frame balances concealment and shootability
- Trusted by law enforcement and civilian carriers
Key Variants
FN 509
Standard full-size pistol, ideal for duty and home defense roles.
FN 509 Tactical
Includes threaded barrel, suppressor-height sights, and expanded optic compatibility.
FN 509 Compact MRD
Shorter grip and barrel for deep concealment and CCW users.
FN 509 LS Edge
Long slide variant designed for competitive shooting with enhanced trigger and performance parts.
Competitor Comparison Table
| Feature | Fn 509 Midsize Mrd | Glock 19 | Sig Sauer P320 |
|---|---|---|---|
| MSRP | $799 | $599 | $649 |
| Capacity | 15+1 | 15+1 | 15+1 |
| Weight | 26.5 oz | 23.7 oz | 25.8 oz |
| Optics-Ready | Yes | No (MOS variant required) | Yes (RX models) |
| Trigger Type | Striker, flat-faced | Striker, curved | Striker, modular |
| Notable Pro | Excellent slide-to-frame fit | Proven global reliability | Fire control group modularity |
| Notable Con | Higher cost | No optic-ready base model | Bulkier grip for some users |
Best Use Cases
- Concealed carry
- Home defense
- Police or security duty
- Range practice sessions
- Optics-enabled handgun training
FAQs
Can I mount a Trijicon RMR on the FN 509 Midsize MRD?
Yes. It comes with a mounting plate system compatible with Trijicon, Leupold, Vortex, and others.
What is the trigger pull weight on the FN 509 Midsize MRD?
Factory trigger pull is approximately 5.5 to 7.5 pounds depending on the lot and model generation.
How does the FN 509 Midsize differ from the Compact?
The Midsize has a longer barrel and grip for better handling and increased magazine capacity.
