About a month ago, I quit tumbling brass in one of those vibrating thingies and switched to an ultrasonic cleaner because I'm concerned about lead contamination when I sifted the brass out of the media. Anyway, liquid cleaning isn't anything new because I've always plopped my BP brass into a tupperware bowl with a weak vinegar mix before giving them a more thorough scrubbing at home.
Except for last New Year's Day. A bunch of my buddies and I did our annual skeet shoot and I fired off a half dozen rounds from dad's old 12 gauge side by side. I tossed everything in the trunk when I was done, but I forgot to do anything with the brass. Until today. Yuck.
After three ten minute baths in the ultrasonic cleaner, they're not just like new, but they're cleaner than I deserve.
I didn't take a picture, but the solution in the tank after the first soak was just plain filthy - it was actually hard to see the brass for the scum.