The extractor grove is part of the retaining wall of the primer pocket. The ring would compress the brass in the groove. Once I tried to modify the clamp on RCBS bullet puller to fit in the extractor groove to see if I could swage down the dia. of the groove to tighen the primer pocket. The piece broke so I abandoned the idea untill I thought of this. RANDY
Ohhh, gotcha'.
Seems to me you'd have problems with the steel ring galling/scraping against the inside the steel die? Also seems that if you swage the overall case then the extractor groove will go with it?
Anyway, I've got your idea now.
al