Hello. I had erratic ejections with my Generation 3 Glock 19, test fire date March 2012. I replaced the stock extractor with the extractor from my Generation 3 Glock 30. The dimensions of the extractor are slightly different but only slightly. The first thing I noticed after installing the G30 extractor was that it held the case firmly against the breech face. The original stock G19 extractor claw touched the case at the angled transition between the rim of the case and the side wall. This allowed for a tremendous amount of play in the case while being "held" by the extractor. Granted, the case doesn't spend much time being held by the extractor during the rearward movement of the slide, but the play was excessive. The casings from the first couple of magazines fired through the G19 with the G30 extractor ejected perfectly. The next 600 rounds ejected perfectly with only a very small handfull going straight back, but well above the shooters head. Any cases using the stock extractor that ejected straight back ejected only a few inches above the gun, basically, they hit me in the face. I consider the gun fixed. I am unsure if the replacement extractor is acting as a band-aid or directly corrected the cause of the symptom but I can't deny the fact that ejection is perfect. For giggles I purchased the Gen 4 ejector with the flat face and installed it into the Glock 19. The ejection with the Glock 30 extractor had reduced ejection quality, though still acceptable. The ejection with the new ejection and the STOCK G19 extractor was as good if not better than with the Glock 30 extractor alone. For my pistol, both the Glock 30 extractor or the Gen 4 9mm ejector ( each alone only ) corrects the erratic ejection I was experiencing. I have discussed this issue in great length with many people in the firearms industry and it seems likely the case is slipping out from under the extractor during extraction/ejection and rotating around it's own center of mass rather than pivoting around an axis under the claw of the extractor and gaining lateral momentum to carry the case out the side of the ejection port. This stationary rotation causes the case to impact the breech in various locations as the slide begins to move forward again which causes the case to be thrown in extremely random directions. There are plenty of slow motion videos on YouTube showing the cases bouncing around in the ejection port. I hope this information helps someone in some way.