FN 509 // SECRET FIX for Your Gritty Trigger

Published on March 18, 2019
Duration: 8:23

This guide details a specific modification for the FN 509 pistol to address a gritty trigger pull. The 'secret fix' involves smoothing the front barrel lug, an often overlooked component that can cause friction. The procedure, demonstrated by an expert instructor, includes careful filing and sanding of the lug, followed by lubrication, resulting in a significantly smoother trigger feel for both OEM and aftermarket triggers like Apex.

Quick Summary

The gritty trigger pull on an FN 509 is often caused by friction from the sharp front barrel lug. The fix involves carefully filing and sanding this lug to create a smooth surface, followed by lubrication. This method significantly improves trigger feel for both stock and Apex triggers, making the pull 'buttery smooth'.

Chapters

  1. 00:00Intro: FN 509 Gritty Trigger Problem
  2. 00:23FN 509 Models & Trigger Types
  3. 01:00The 'Secret Fix' Discovery
  4. 01:30Initial Troubleshooting Attempts
  5. 02:20Identifying the Barrel Lug 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 pull on the FN 509?

A gritty trigger pull on the FN 509 is often caused by friction from the sharp edge of the front barrel lug rubbing against the trigger shoe. This is an unexpected source, as many assume the issue lies solely within the trigger mechanism itself.

How do you fix a gritty FN 509 trigger?

The fix involves carefully filing and then sanding the sharp edge of the front barrel lug on the FN 509 to create a smooth surface. A small amount of lubricant applied to the lug after smoothing further enhances trigger feel.

Does this FN 509 trigger fix work with Apex triggers?

Yes, the barrel lug smoothing modification is effective for both the stock FN 509 trigger and aftermarket triggers like the Apex trigger. It significantly improves the smoothness of the pull regardless of the trigger type installed.

What are the trigger pull weights for the FN 509?

The stock FN 509 trigger pull weight typically measures around 5.5 lbs. An FN 509 Tactical equipped with an Apex trigger can achieve a lighter pull weight, often around 4.5 lbs, after modifications.

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