I was shooting a new 1911 I finished, and I had the same problem three times... before the last round chambered, it ended up standing straight up in the ejection port. (Is that a "stovepipe," or is that only for an empty case?)
The fact that it's only happening with the last round - can that help me narrow down what the problem is? Any ideas?
First off were you only shooting out of one magazine and if you were shooting several was it always the same magazine that gave you problems. I number my magazines to help me eliminate problems that are magazine related. First thing I would do is replace the recoil spring if it is not brand new with a 18.5lb wolf. Next reshoot it with several good brand name magazines. It could be several things but magazine or recoil spring is the first thing to come to mind in my opinion.
Good thing I asked. I was about to start playing around with the extractor tension, and I hate going back and forth with that.
The magazine I was using is a good one - feeds fine in other guns, but it's not the best I have. I'll try another mag and a stiffer recoil spring and see what happens.
Yea I doubt its the extractor tension if its only ever the last round that gives you the problems. Whenever I have a problem 1911 I go out with several magazines of different makes and ensure they are numbered. You will find some 1911's like one vendors magazines over another many times. I have Wilson, Wolff, Novak and Colt magazines and plan to get some TRipp magazines real soon as you never know what magazines your gun is going to like and it sounds more lilke a magazine problem than anything now that I think about it.
Just try the mags then change the recoil spring .Don't change the spring then try the mags, if the problem stops, you don't know which of your changes was the answer. I learned this from doing the first actions suggested and never did find out what solved my problem. Just replace or test one thing at a time.