FN 509 // SECRET FIX for Your Gritty Trigger

Published on March 18, 2019
Duration: 8:23

This guide details a specific gunsmithing fix for a gritty trigger in the FN 509 pistol. The expert-level instruction from Tactical Toolbox focuses on identifying and smoothing the barrel's front lug, a common source of friction. The procedure involves light filing and sanding, followed by lubrication, to significantly improve trigger feel on both stock and aftermarket triggers.

Quick Summary

A gritty trigger in the FN 509 pistol is often caused by friction from the barrel's front lug against the trigger shoe. The fix involves carefully filing and smoothing this lug with a fine file and sandpaper, followed by lubrication, to significantly improve trigger feel. This method works for both stock and aftermarket triggers.

Chapters

  1. 00:00Intro: Gritty Trigger Issue
  2. 00:23FN 509 Models & Trigger Types
  3. 01:00The 'Secret Fix' Discovery
  4. 01:30Initial Troubleshooting Steps
  5. 02:20Identifying the Barrel Lug as Cause
  6. 03:30The Fix: Filing the Barrel Lug
  7. 03:54The Fix: Sanding and Lubricating
  8. 04:30Post-Fix Trigger Feel
  9. 04:53Trigger Pull Weight Comparison
  10. 06:10Final Comparison & Recommendation
  11. 06:57Conclusion & Call to Action

Frequently Asked Questions

What causes a gritty trigger in the FN 509 pistol?

A gritty trigger in the FN 509 is often caused by friction from the barrel's front lug rubbing against the trigger shoe. This issue can persist even with high round counts or aftermarket triggers like Apex, and is not always related to internal trigger mechanism wear.

How can I fix a gritty FN 509 trigger?

The fix involves carefully filing and smoothing the sharp edge of the barrel's front lug with a fine file and 400-grit sandpaper. Applying a small amount of lubricant to the smoothed lug further enhances trigger smoothness.

What is the typical trigger pull weight for an FN 509?

A stock FN 509 Standard typically has a trigger pull weight around 5.5 lbs. An FN 509 Tactical with an Apex trigger, after the barrel lug fix, can achieve a lighter pull weight of approximately 4.5 lbs.

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