The FN 509 Full Size pistol in black with a 4.5-inch barrel and 10-round capacity (brand part no. 66-100718) is a full-size, duty-grade double-action-only 9mm, with a magazine configuration built for added-regulation states. FN America cuts the slide for optic mounting and serrates it for a positive grip, and adjustable sights support precise target acquisition. This configuration ships without a manual safety, relying on the double-action-only trigger, with two magazines included. Among full-size semi-auto handguns, this 509 configuration favors duty use in added-regulation states.

Key Specifications

• The chambering is 9mm.
• The capacity is 10 rounds.
• The barrel measures 4.5 inches, finished in black.
• The trigger action is double action only.
• The slide is optic cut and serrated, ready for a red dot.
• The sights are adjustable for precise aiming.
• Two 10-round magazines are included, built for added-regulation states.
• A No Manual safety is featured.
• Shipping weight of approximately 3.4 pounds.

Frequently Asked Questions

What trigger action does this pistol use? A double-action-only trigger.

Why does this configuration use 10-round magazines? It’s built to meet added-regulation state capacity requirements.

Buy the FN 509 Full Size Pistol, 10+1

Full-size, double-action-only 9mm performance built for added-regulation states is exactly what this 509 delivers. Order it from our Lubbock, Texas gun shop for fast, insured shipping to your FFL.