Originally Posted by molar
I detail stripped my gen 3 17, gen 2.5 26, and problematic gen 3 19 slides and measured from the front edge of the extractor channel to the opposite external surface of the slide. There were no appreciable differences in the dimensions. I don't think the problem lies with the depth of the extractor channel. I still think the extractor is situated too far from the breechface. Due to the angle of the cut in the slide, it appears that filing down the extractor pad per Dave's recommendations would not only apply more biting force to the case rim, but would also swing the extractor in towards the breechface a little. The pad that needs filing is 0.023" on my extractor. I think I'll take off 0.012 and see what it does.
By coincidence I field stripped my Glock 19 Gen 4, my M&P FS 9mm, and my Kahr CW9 at the same time. Both the M&P and the Kahr eject perfectly, and will eject normally with the mag out (the "1911 test). I lined the slides up together to see if there was a difference in the gap between the breechface and the claw. There was no difference that I could see, although I have no way of measuring precisely.
I don't think there's anything wrong with doing what you suggest as long as you don't take off so much that you cause feeding problems. I would suggest removing .006" and see how it's feeding before taking off the other .006".
I don't think taking material from the pad will, in and of itself, do any good. If the claw is at the bottom of the groove in the cartridge head with the case where it would be in the linked down position, and if removing the case allows the claw to move in even a little bit more, then lack of inward travel is not the problem. Allowing it to move inward more will not put more tension on it when the spent case is at its lowest position. A stronger spring will. Or a SLB with a longer "head" will.
If you put an empty case in the extractor so that the case is near the bottom of the extractor, where it will be when it's being ejected, you will see that the case, not the pad on the extractor, limits the inward travel of the extractor claw.
However, having said all that, there's nothing wrong with experimenting as long as you have a spare extractor on hand in case you cause feeding issues. If I am wrong and your idea works, of course I'd like to know about it.
I have three spare extractors, two new non dip Glock and 1 LWD, arriving later today. I intend to do my experiment with one of the non-dip Glock ones as soon as they arrive. What I'm going to do is remove material from the edge of the claw to make it parallel with the opposite side of the slide, recut the groove and trim the front of the claw as needed, and then take a bit off the pad, but just enough to keep tension on the case. Since there is already tension on the case in the linked down position, I don't think I'll need to take .012" off the pad: probably more like .002"to .004". I will then make a new SLB to put more tension on the claw and move the EDP forward to compensate for the material I have removed. I already have a White Sound Defense extra power EDP spring in there, and spares in case I compress it too much and deform it.
I believe, along with Randy Lee, that taking the angle off the claw and putting more tension on it will help. My goal is to make this gun pass the 1911 test. Even though it has never jammed, the fact that it will not pass this test bothers me. I would like to see this gun eject as predictably as my other 9mm pistols.
Assuming the Fedex truck gets here in time, I will make my modifications and go test them at the range all later today. I will post results. If I did any good I'll post photos.