Looks like I should look stuff up, before I start answering questions.
According to
this link its steel cartridge cases that could cause an extractor to be too tight. Looks like obstructed chamber and dented cases could cause your problem too, but we can probably rule those out. Anyway, that is a good site with lots of valuable 1911 info.
http://www.sightm1911.com/lib/tech/malfunction.htm