Do-it-yourself Finger Groove
origonaly posted by bigbird on the KTOG message board.
Here is a freebie mod that has most of the same benefits as (or in addition to) a magazine extension. It gives you better 'indexing' of the grip into your hand, helps you create a more repeatable grip, and can reduce "limp-wristing" if it is actually a too-light hold. This mod won't compromise the concealability of the P3 at all and you need no tools but files and sandpaper.
See the picture - the finger-stop is the small piece of plastic glued to the grip right between the second and third fingers.
To make the piece, take a small piece of flat black plastic about 3/16-1/8" thick, and use a round needle file to cut two half-circles into the edge, of around 1/4" radius, and spaced on 1/2" centers. File the bottom of the two cuts straight across untill you have a dent 3/4" across and 3/16" deep that looks like a crescent with a flat in the middle. This cut into the edge of the plastic should more-or-less match the profile across the front strap of the grip.
Next, fit it to the grip - wrap some 600-grit sandpaper around the front side of the grip, and sand the indent up and down until it is a good match when you fit it to the front of the grip without the paper (little or no light visible between them).
Now you can cut or file around the dent you created, and sand the outside of the finger stop into any shape you like. I made mine flat across the front because the flat fits in between my knuckles while the 'corners' are between the flesh of the fingers (and because I liked the way it looked).
Finally, hold the gun as when shooting, to determine exactly where the middle of your second and third fingers falls on the grip - mark it with a pencil. (For me, the finger stop is just right when located about 1/8" above the 'bend' in the front strap.) Check the location a few times, as superglue is pretty permanent. Hold the piece at that location between your fingers with your grip on the gun to be sure.
Once you are sure where you want it, put a THIN layer of any superglue on the inside surface of the piece, and press it in place for 30 seconds. If you use too much glue, a quick cleanup with acetone can remove it without damaging the surface of the grip.
As you can see, it looks like an original part of the grip.
The Handall has built-in finger grooves - Uncle Mike's don't, so this mod can be useful with or without a rubber grip sleeve.
As to a souce for plastic, I used a piece of a plastic box that something or other came in. If Acetone etches it or superglue sticks to it, it will do the job.
Polyethylene, like the Glock sandwich box, doesn't work, because its waxy characteristic doesn't stick to any reasonable glue - try a piece of candidate plastic with superglue - if it's black and it sticks, it's OK for this.
CD jewel case plastic is about 1.5 mm thick (most are grey, but maybe 10% are black). A little thicker would allow more sculpturing of the piece, but isn't really necessary for function.
The whole idea here is simply to customize the grip to your hand, so whatever works...
yzguy - steal away - that's why I wrote it up. BTW, the magazine extension is a sawed-off NAA - sanded back so it doesn't compromize concealability so much.
This is a good idea if you don't like the Handall JR (some don't).
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