Welcome to Glock.pro Mudbutt... That's quite a screen name...Just purchased 1 after not owning a glock for many years. What can I expect from a Gen4?
Some of the early 4th gen Glock 19's had an overly aggressive recoil spring assembly... They had some difficulty shooting ultra light 9mm ammunition... mostly the Winchester White Box and Federal Champion 115ge FMJ ammo sold by Walmart...
Glock revised the recoil spring assembly and will mail you the new one for free if it turns out you don't have the latest version...
I have a 4th gen 19 and love it...
