a few months ago I started putting my breech plugs, nipples, plungers (older style inlines hammers) and sometimes trigger groups into my sonic cleaner to well cleaning.

just dawn and hot water and let them run for about an hour. all the crud is either in the bottom of the cleaner or just whips off.

I've thought about doing that. If I ever get around to buying one of those things, I will do that. I use ultrasonic cleaners at work.