Apex Tactical Action Enhancement Trigger Kit for FN 509 - Precision Aluminum Upgrade

If you've run a few hundred rounds through your FN 509 and thought "the trigger could be better," the Apex Tactical Action Enhancement Trigger Kit for FN 509 is a straightforward way to fix that. This drop-in trigger upgrade swaps out your factory plastic trigger assembly with machined aluminum internals that deliver a lighter, crisper pull with noticeably less take-up and a faster reset. It's the kind of refinement that pays off at the range and in a defensive scenario—and because Apex engineered it as a bolt-on job, you don't need a gunsmith.

The kit replaces three factory components: the trigger shoe, trigger bar, and sear. The new trigger sports Apex's signature flat-faced design machined from aluminum, finished in matte black hard-anodize for durability. The sear and trigger bar are polished stainless steel, designed to work together smoothly and consistently. Trigger pull weight comes in around 5.5 lbs once installed, though individual examples may vary slightly depending on your specific pistol. All four factory safeties—trigger safety, firing pin safety, drop safety, and out-of-battery safety—remain fully functional; Apex's kit doesn't bypass or degrade any of them.

This is a DIY-friendly project if you're comfortable with basic gunsmithing and can follow detailed instructions. It fits both 9mm Luger and .40 S&W FN 509 models and comes in three finishes: Black, Red, and FDE. If you prefer a trigger that feels more refined than the factory Glock-style plastic unit and want a noticeable performance boost without modifying your pistol's safety architecture, this upgrade makes a solid choice.

Key Features

• Drop-in replacement for factory trigger assembly—trigger shoe, trigger bar, and sear
• Machined aluminum flat-faced trigger shoe with matte black hard-anodized finish
• Polished stainless steel sear and trigger bar for smooth, consistent performance
• Reduces trigger pull weight to approximately 5.5 lbs
• Shorter pre-travel and pull length with faster reset than factory trigger
• Does not alter function of any factory safeties (trigger, firing pin, drop, or out-of-battery)
• Compatible with FN 509 in 9mm Luger or .40 S&W
• Available in Black, Red, and FDE finishes

Specifications

Frequently Asked Questions

Will this trigger kit work with my FN 509 in .40 S&W?

Yes, the Apex Tactical Action Enhancement Kit is compatible with FN 509 pistols chambered in both 9mm Luger and .40 S&W.

Do I need a gunsmith to install this trigger kit?

No. Apex designed this as a drop-in replacement that shooters comfortable with basic tools and detailed instructions can install themselves. It replaces the trigger shoe, trigger bar, and sear—no gunsmithing required.

Will installing this trigger affect my pistol's safeties?

No. The kit does not alter the function or reliability of your FN 509's factory trigger safety, firing pin safety, drop safety, or out-of-battery safety. All safeties remain fully operational.

What finishes does this trigger kit come in?

The Apex Tactical Action Enhancement Trigger Kit for FN 509 is available in three finishes: Black, Red, and FDE.