Go to your local car parts store and pick up some brake cleaner in the arisol can, put the plastic tube on and stick it up into your resizeing die and spray out the build up of crud, " wear eye protection, burns when you get the spray in your eyes" after it sits a few minutes the spray evaporates leaving it sparkling clean. By the way! you might try RCBS pump spray lube next time, to me it seems to work better without the waste of the overspray and the tip clogging and causing it to spit!