Not saying it couldn't be the extractor, of course.
But I ran into a similar deal last year. Local guy got a prefit barrel for a 700 and after installing it, the extractor wouldn't pull the case. I took a look and what he thought was the chamber head spacing on a new piece of brass (first mistake) was actually the bolt nose jamming into the counter bore in the barrel as it wasn't machined deep enough (barrel plumbers mistake). Even after being set with my head space gauge, extraction was iffy. The extractor groove on the new brass was a little bit forward from his old brass and the base to datum on the new brass was .006 shorter than his old brass. Not surprisingly, the old brass worked fine. So all this added up to point to the extractor not working.
Of course, It wasn't the extractor at all.
After getting everything squared away on it, the bolt nose clearance was still too tight...right at .003. I addressed that for him and all was good.
The fact that O.P.'s extractor is
not able to be rotated is a good thing.
I mention this only because the bolt could be sent away for a new extractor and it might still not work if there's other stuff involved. Like always, check everything and understand how everything fits together and has to work together. The glut of prefit barrels...some of which are truly nasty things...cause 'way more problems that you generally hear about. The good ones can be a fine way to do it and the bad ones will make a shooter wish their father had never met their mother.
Just sayin'.....
