I finally got to put a few rounds through my AT after replacing the extractor a month or two ago. Result: 50 rounds of UMC FMJ, 2 FTE, 1 FTF. I guess I start doing some polishing of the chamber and more feedramp work... and looking into modifications for the extractor. That should put an end to it. The FTEs were far less frequent than with the old extractor but it's still not reliable enough for me to count on in a carry situation. The one FTF was easily solved by slapping the slide home.