immediately after firing, .45-70 cases go into a jug of plain water that has a squirt of dawn dishwashing soap - this is a
most important step in order to keep the bp residue soft. back at the ranch, the brass is washed with tap water, the primers are pulled with a harvey hand deprimer, brass is rinsed again then into the ultra-sonic for 30 minutes, rinsed in tap water, cloth or paper towel dried, done ...
(NO, these are not new brass - these have already had over 6 firings)
https://i.imgur.com/VbsMVSZ.jpg