Originally Posted by dhgeyer
The rub marks on the EDP has been noticed and discussed in other threads. I don't know if there is a consensus on this (what causes it and what it does), but I have my opinion. It happened to mine also. I noticed it after JBS pointed it out in another thread. My gun had about 500 rounds on it at that point. I can't say when it would have become visible had I been watching for it. I attribute this wear to a sharp edge on the front of the extractor assembly channel in the slide and the hardness of the slide. In my gun the original EDP is a loose enough fit in the channel that I would rule out binding.
JBS said that he has seen guns in his shop that had wear in this location that would almost surely impede steady tension on the extractor. I think that might be one small piece of the puzzle of why extraction/ejection can go bad on these guns after X number of rounds.
This is why I zoomed in on it for the photos on Facebook.
My Gen 4 G23 with 2k trouble-free rounds through it has no visible wear whatsoever on the bearing. Is this significant? I don't know...