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Old 04-06-2007, 6:55 PM
leelaw leelaw is offline
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OK, the official Leelaw Methodô FN Five-seveN Magazine Disconnect Disable.

Note: I do not warrant any of the work performed within this tutorial. However, I have had absoloutly NO failures of any kind since I performed this modification to the Magazine Disconnect on my FN 5-7 IOM, and have every expectation that it will work the same for your pistol as it has for mine. Again, I make no guarantees about this, for legal reasons.

On to the tutorial.

I purchased a FN Five-seveN IOM about two years ago, and was overall pleased with the gun except for one feature - the magazine disconnect. A magazine disconnect is, in my opinion, a safety issue, since it could be possible, however remotely, that I need to fire the gun when between reloads, without a magazine inserted, and with a round in the chamber. The magazine disconnect, by virtue of its design, would prevent me from doing exactly that. So I set out to disable mine in such a way that it could be done without damaging the mechanics of the pistol, and also be reversed if need be.

First, the magazine disconnect for the FN Five-seveN must be explained a little bit.

There is a tension bar (it will be pictured/explained in pictures below) which puts downward pressure on the linkage between the trigger and sear. When this tension bar does as stated, it disconnects the trigger linkage from the sear and prevents the striker from falling.

When a magazine is inserted into the magazine well, a "shelf" (for a lack of a better term) on the right side of the magazine pushes UP on the tention bar, allowing the trigger linkage to raise upwards, too. When the trigger linkage is in this upward position it reconnects with the sear and will allow the striker to fall when the trigger is pulled.

Once I recognized the way the magazine disconnect worked, I set out to fix it, and did so, in the most simplistic terms, by manipulating the position of the tension bar so that it always puts upward pressure on the trigger linkage, and always allows the hammer to drop when the trigger is pulled.

On to the method:

1. Engage the safety of the Five-seveN
2. Completely empty the firearm - empty the chamber, and remove the magazine. DO NOT ATTEMPT TO DO THIS OR ANY GUNSMITHING ON A LOADED FIREARM! I can not be held responsible if you injure yourself from attempting this modification.
3. Remove the slide from the frame.

The inside of your firearm should look like this.
Explanation of the parts:
Lower Tension Bar Retainer
Tension Bar
Upper Tension Bar Retainer
Trigger Linkage

Note how the Tension Bar is held in place by the Upper and Lower Retainer. These pieces are plastic and are not in any other way attached to the Tension Bar, other than simple friction. Also note that the Tension Bar is pushing downward on a little "finger" at the bottom of the Trigger Linkage.

4. Insert a small jewelers flat-bladed screwdriver, between the Tension Bar and the frame of the pistol, and gently pry the Tension Bar toward the opposide side of the frame.
5. When the tension bar has cleared the Upper Retainer, use pliers or your finger to pull it upwards, towards where the slide would be.
6. Let the Tension Bar rest on TOP of the Upper Retainer, putting upwards pressure on the Trigger Linkage.

Your pistol should now look like this.

7. Reinstall the slide.
8. Check to make sure that the firearm is completely unloaded.
9. Check for proper function of the firearm. While pointing the firearm in a safe direction: Disengage the safety and pull the trigger, releasing the striker; cycle the slide; pull the trigger, releasing the striker, and hold down the trigger; cycle the slide; release the trigger, noting that the trigger reset functions properly; pull the tirgger, releasing the striker; cycle the slide; engage the safety and pull the trigger - if your striker falls at this point, something was done wrong and you should have your pistol checked by a professional gunsmith immediately!

I hope this has been informative. The modification should be 100% reversible (I verified this today) and your firearm will not be damaged by it. I've put almost 1,000 rounds through my Five-seveN since performing this modification and it has run 100.00%

Disabling the magazine disconnect this way requires NO modification to the magazines.

Please PM me with any questions you may have.
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