A long time ago I must have loaded and shot cast bullets with Unique and just put them back in the original styroform box. [the cases were filthy] Yesterday, when I resized them to load again, I was getting sort of a film or like a very light skin of a residue coming off the case. I started to wipe them with a rag but, the cases felt kind of sticky. They are not primed yet, but, I would sure like to clean them again and I know what a pain it is to dig the media out of the flash hole.[made that mistake too] So, hoping that that film will not end up in the revolver cylinder and be more difficult to remove I was hoping I could clean primed cases without any unforseen problems.