How much can you undercut from a polymer frame

[hermosabeach]

https://m.youtube.com/watch?v=HElQk2wEY5w

You see the trigger guard deforming a bit during recoil.


How thin can you cut the trigger guard before you risk it breaking?

[smittty]

Reduce to half the thickness.

[SkyHawk]

Go all the way

[JTROKS]

I usually don’t go thinner that .090” on Glock trigger guards when grinding/milling the relief and under cut.

[hermosabeach]

Are there many cases of the trigger guard breaking from being overly undercut?

[morrcarr67]

That looks ridiculous.

Go all the way

[223556]

Looking at the video it appears to be a Sig Pro with no modifications to the trigger guard.
I’ve seen videos of Glocks as well with the same flex the Sig is showing.
Dunno what the max amount of polymer one can remove before compromising the frame.

[sonofeugene]

Most reductions of material I've seen take it way too far. And I should also point out that the trigger guard need not be reduced throughout its thickness. All of one needs is a little angled cut on the right side (if you're a right handed shooter) to give you the relief you need for comfort. The middle of the guard can remain full thickness.

Next time you pick up your gun, grip it as you would if you were going to shoot it and point it at a mirror. Now look at the angle your finger is at compared to the bottom horizontal edge of the guard. You'll see what I mean.

[Dano3467]

I guess my 1st question would be is, WHY ?

[sonofeugene]

On some guns, the guard can be a little on the sharp side.

[hermosabeach]

bore axis

I guess my 1st question would be is, WHY ?

To get a higher grip on the pistol...

because you have dainty hands and don't like the frame rub...

[Wheellock]

It would be interesting to see that slow motion done with a heavy light hanging on it...or a rail mounted comp

[FNGGlock]

Are there many cases of the trigger guard breaking from being overly undercut?

Lots of people have cut Glocks as they do have a thick trigger guard. Not heard of any breaking.
Though you only need to take a little to improve comfort and grip. On mine you have to look carefully to even notice it.

[SharedShots]

Before you start undercutting make sure the problem you want to solve is really the trigger guard and not the fit of your hand down lower. Here is why I say this:

On the Gen3 you have the finger groves and with some models like the 19/23 there is sometimes a tendency to want to get the small finger onto the grip which then crowds the other fingers upward. The thought is that by undercutting the trigger guard that it solves the problem by giving you more room when it really doesn't. With the slightly different grips on the Gen 5 for example, this doesn't present itself the same way.

If you undercut the trigger guard and then your middle finger moves upward slightly that can also cause pressure on the trigger finger to move slightly upward and it doesn't take much to affect control.

Check your handgrip. Keeping the trigger finger out of the guard and pointing parallel to the slide look between the knuckle and first finger joint for the trigger and middle finger (normal grip). If there is no gap or only a very thin one, undercutting the trigger guard isn't the problem and cutting it will likely have a detrimental effect on trigger control as your index finger will be pushed up slightly and then angle down a very small amount during trigger operation.

To test further, ignore the position of the small finger, pretend it doesn't matter. You can tape a popsicle stick or something like that as a split to keep it straight out and then grip your pistol. Do you still feel the crowding or does it no longer matter? You might find that it's not the trigger guard at all and you're chasing something that won't help. Maybe a mag extension (keeping in mind round capacity) gives you the small finger support you want.

Don't forget, once you cut the trigger guard that's it, there is no going back easily or cheaply. There is sometimes a tendency to want to grip the pistol higher when that can make your index finger angle down when controlling the trigger. It should the a parallel and straight pull on the trigger and then you won't have to adjust your grip after each shot or at least not as much.

Before you go cutting away at your own pistol, find someone else who went at theirs because an idea is cheap but a dremel is priced into the new gun because you hacked up the old one.

[boopiejones]

Most reductions of material I've seen take it way too far. And I should also point out that the trigger guard need not be reduced throughout its thickness. All of one needs is a little angled cut on the right side (if you're a right handed shooter) to give you the relief you need for comfort. The middle of the guard can remain full thickness.

Next time you pick up your gun, grip it as you would if you were going to shoot it and point it at a mirror. Now look at the angle your finger is at compared to the bottom horizontal edge of the guard. You'll see what I mean.