I've been using my kitchen dishwasher for cleaning my cap 'n ball revolvers for over 20 years with zero issues.
I first remove the nipples & grips - then disassemble into the major parts for distribution into the top rack of an otherwise empty dishwasher.
I use whatever diswashing detergent my wife uses.
I stop the dishwasher, by opening the door, at the end of the first wash/cycle - and remove the very hot metal parts from the washer.
I close the empty washer, to finish running through it's other multiple wash/rinse cycles - insuring a safe/clean enviroment for my family's eating utensils to be handled in.
The heated gun metal parts evaporate any moisture rather rapidly - I oil everything, as soon as they're dry to my eye, and re-assemble, ready until my next shooting session.
I clean the nipples separately, by hand, under a tap of hot running water.
FWIW, I also clean my empty/deprimed fired rifle/handgun brass, stuffed in a pillow case, in my clothes washing maching, along with a load of towels - but, that's another story.
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