I look at dies as a pretty small investment, and only worry about really dirty cases...ones that hit the mud. I wipe them off. If they were plucked from the chamber or just landed in the grass, good to go. I do use the tumbler to remove the lube after sizing.....sometimes just enough to get the lube off if I want to get them loaded soon, longer in the tumbler if I have time. I may be damaging the dies...but if a sizing die ever goes bad, I'll replace it, probably with a new set of the Redding dies I've seen advertised that come with the better expander plug and micrometer seater. I have a hunch I won't need too many of those sets, though.
