The FN 509 LS Edge is a semi-automatic handgun chambered in 9mm Luger (9x19 Para) with a double action only trigger. It has a 5-inch barrel, holds 10+1 rounds, and weighs approximately 31 oz. The frame is black matte polymer with a textured grip and interchangeable backstraps. The slide is graphite PVD steel. No manual safety; ambidextrous controls are included. 
 

Key Specifications 

• Brand: FN 
• Model Name: 509 LS Edge 
• Caliber: 9MM Luger (9x19 Para) 
• Action: Semi-Automatic (Double Action Only) 
• Capacity: 10+1 rounds 
• Barrel Length: 5 inches 
• Weight: 31 oz (approximately) 
• Frame Finish: Black Matte Polymer 
• Grip Type: Black Textured with Interchangeable Backstrap 
• Safety Features: No manual safety; ambidextrous controls available 
   

Detailed Features 

1. Target Crown Barrel: The recessed target crown helps maintain consistent muzzle performance shot to shot. 
    
2. Fiber Optic / Blackout Sights: Fiber optic front sight paired with a blackout notch rear gives good contrast for fast target acquisition across lighting conditions. 
    
3. Graphite PVD Steel Slide: Corrosion-resistant finish holds up well with regular use. 
    
4. Interchangeable Backstraps: Lets you adjust grip circumference to fit your hand. 
    
5. Ambidextrous Controls: The slide stop and magazine release are usable from either side.

The FN 509 LS Edge gets a generally positive reception among owners who focus on competition or precision work.

Accuracy and build quality are the two most consistent positives. The 5-inch barrel and target crown contribute to tight groupings, and the materials feel solid. The grip ergonomics work well for most shooters, and the controls are considered intuitive. The trigger pull gets mostly favorable marks - smooth with a clean reset - though experienced shooters sometimes want it a bit lighter. The optics-mounting options and customization potential appeal to users who like to tailor their setup.

On the practical side, the full-size frame makes it a poor choice for everyday concealed carry, and that tradeoff comes up often. Price is the other recurring note; some buyers find it on the high end compared to competitors with similar specs.