Partner here at OHP just bought a Gen 4 G19 and has shot about 600 rounds with no problems. In fact when we were at the range three weeks ago I watched him shoot about a hundred rounds with zero problems. I have about 2000 through my Gen 3 G17 and no problems. Thats between factory and my reloads. You might try taking it completely down and cleaning it then oil it and see if it makes a difference. Just a thought.