I ran some through my GP100 yesterday and was a bear to extract. I had to whack the ejector rod with the handle of my demooner to get them out.
Running factory moons, it would sometimes start to drag after four rounds. Then I noticed the last two bullets slipping their crimp.
It wasn't the clips, either. I ran a couple cylinders without moons. Still hard to extract.
I mostly run .40s in this gun, but I've shot Sig 10s before with no problems. The cylinder was squeaky clean at the start of the session.