I am going to look at a Glock this weekend, I know the Glocks are designed to handle +P.
I was hoping that the worst case scenario for loading 9mm hot would be the commercially availble +P+ like Buffalo Bore.
I guess I am worried about the previous owner fired hot ammo through it and was hoping that you couldn't make 9mm so hot that it would damage a Glock - but that's too much to ask for I guess.
Someone could always load to +P+ pressures with regular brass and blown it up I am guessing...
The pressure is not likely to cause wear on the Glock, recoil is.
The Glock 19 with too much recoil has the slide hit the frame.
Here is a Glock 19 that has shot a lot of hot 9mm ammo, much hotter than any +P+ commercially available.
In the pics I have tried to label, in red, the two surfaces that collide when there is too much recoil.
It is ~ a 12 ounce slide hitting an ~ 5 ounce frame.
If your hands were made of metal, the frame would take a much bigger beating, but the compliance of your hand's web allows to frame to move.
Can you see a slight deformation of the plastic frame?