Here is my issue. My G19 Gen 3 slide will not stay open after the last round. It is a gen 3. I have a G17 and shot them side by side thinking maybe it was my thumb hitting the slide release, its not. My G17 has not problems. Next, I tested several different types of ammo thinking maybe the ammo was too weak. I tried my +p Double Tap defensive ammo and after the last round it still did not stay open. I took the slide off and inserted an empty mag to see if the mag pushed up on the slide release and it did so there is no problem with insufficient spring "push". This is happening with about 95% of my mags. This Glock is brand new and these mags are Gen 4 mags. Did I maybe just get a lemon and I need to send it to Glock. Is there anything else I could do to test it out?