How to improve your trigger function by

installing an overtravel stop in both pull and release.

Tools and equipment needed:

An acetylene or mapp torch, silver solder, epoxy glue or Loctite, a drill and drill bits, suitable pieces of brass tubing/rod and plate, needle files, needle nose pliers, a couple of screwdrivers to aid in assembly / disassembly. A lathe is preferable if available. Otherwise the sleeve part will need to be outsourced.

If you assemble your trigger mechanism incorrectly it might cause misfires, or other malfunctions. Beware that the only safety device in the triggergroup is that the trigger is blocked. Altering the shape of any of these parts or removal of material *might* render the trigger mechanism unusable at best, or right out dangerous in worst case.

If you choose to proceed, you do this on your own risk, and if you somehow manages to break or otherwise ruin your trigger mechanism or parts thereof, well that is your problem. If you are not 100% sure that you can manage to do this, don't do it, or pay someone competent to do it for you.

1. Modifying the trigger.

This modification will remove rearwards overtravel.

The modification consist of silver soldering a piece of brass to the notch in the trigger that is engaged by the safety selector.

It can of course be welded steel, but I found it easier to use silver solder/brass due to it requires less heat, and the brass is easier to shape when fitting the pieces together afterwards. Be careful when applying heat so that the heat treated parts engaged by the sear don't get too hot.

Fitting:

File the brass piece down in small increments to  the point that trigger travel ends just after the hammer is released. To find this point will more than probably reqiure that the trigger mechanism is assembled and disassembled several times.

Test the trigger action several times to make sure the trigger releases the hammer each time it is pulled.

Note that this modification will remove the full auto function if done to a FA trigger mechanism, as the FA function needs the longer trigger travel to hold the sear clear of the notch in the hammer.

2. Modifying the trigger housing.

This modification will remove the forward overtravel.

This modification consist of making a brass sleeve for the forward travel stop bolt. The sleeve itself has an outside diameter of appx. 6.5 milimeters and an inside diameter of 5.0 milimeters. The length should be  about 2.5 - 3.0 milimeters.

Fitting:

Remove material from the area A in the above pic in small increments to  the point that it don't impede on trigger rearward travel. To find this point will more than probably reqiure the sleeve to be removed and installed several times.

Remove material from the area B in the above pic flat in small increments to  the point that trigger forward travel ends just after the sear engages the trigger. This is easibly recognised by an audible "click". To find this point will more than probably reqiure the sleeve to be removed and installed several times.

Test the trigger action several times to make sure that sear engages the trigger each time. When the trigger functions flawlessly, attach the sleeve with epoxy glue, Loctite 640/660 or similar.

Another trick is to use an MP5 trigger spring in the G3 to get a lighter trigger pull, but this will normally cause the odd misfire in surplus ammo due to the hard primers used in military ammo. This modification should work fine with commercial ammo with softer primers.