+P and +P+ are higher pressure and higher velocity.
Glocks will shoot these forever. I run nothing but +P+ factory and reloads in my Glock and my SIGs.
My G-17 has digested over 12000 +p and +P+ and shows no signs of wear.
For those who have fought for it, freedom has a taste the protected will never know!
Or at least they did before political correctness