75D PCR, After about 800 flawless rounds, I had a failure to eject, then at about 950 had another. Fired case stuck in ejection port blocking new round.
I always clean the pistol after a range session, so I started looking for causes. Read that detritus could build up under the extractor & cause this problem.
SO, I drifted out the extractor pin & cleaned the extractor channel, spring area and the extractor. What I found was a buildup of black carbon and bullet lube from the lubricated lead bullet reloads I used. Most interesting was the buildup inside the hook that engages the rounds case. there was a significant amount there that clearly would keep the extractor hook from fully engaging the case rim. I also deburred all sharp outside edges of the extractor, smoothed both sides of it and re-installed it.
Pistol is now back to its normal flawless operation.
Worthy of note, if lubricated lead bullets are used, check the extractor hook for buildup. AND as I have done, move on to Hi Tech coated lead bullets in addition to the jacketed hollow points I practice with.