OK so it seems to me that I'm the only gen4 glock 19 owner that is having this issue. When shooting the pistol the slide will not lock to the rear. What the HECK?????? Of course I shoot the famous federal 115 and Win white box for range ammo and no matter what drills I'm practicing the slide continues to stay forward. Meaning shoot a half mag and practice reloads or shooting a whole mag for accuracy its stays forward. Now with that said when I was doing ammo test with my carry rounds (hornady 147gr XTP) I did not have this issue. Is it a low grain ammo problem? Regardless if it is or not the gun should function with all type of ammo.