[SoonerPast]

It will take patience

to figure out what the problem is. Kimber's with the external extractor have exhibited a tendency toward problems (understatement). The failure to extract and eject is a too common complaint. The failure to feed the next round is another potential fault of the extractor.

Sending it back to Kimber may be your only option. I'm not familiar with the model you have but with the "Pro" designation, it must be a 4" barrel. The shorter barrel pistols seem to be the most likely to have these problems.

Do a search on "fte" "extractor" "failure to feed" etc. will yield some reading for you.

 

[SoonerPast]

I think internal extractor is better but,

I have a new Kimber I'm trying to fix. The gun jams after an extended period of shooting (like an IPSC match). The spent casing gets stuck really tight in the extractor (internal).

My current theory is that the extractor needs to be held more snugly in its tunnel. The firing pin stop in my gun is also a pretty loose fit. I thinking that the extractor may be rotating a very small amount, but enough to be canted so that the rim of the casing is lodged in the extractor's lip to tight for the ejector to overcome.

The only point here is that if it were able to rotate between an ejection and next round load, it might not be able to ride over the new rounds case rim. But if it is always the last round in the magazine, the ejector may not have anything to do with the problem.