I took a look in classics & stickies and found just a little bit of info on this. I sure don't want to be "Little Billy" (ha-ha)!!!
For years I have not tumbled my pistol brass, preferring to wipe them down either at the range (when possible) or at home when prepping. Sometimes not at all for a few loadings.....
I know I am not the only person out there who does not tumble. In the past, I have played around with washing them using different detergents/soaps/vinegar and the like, but I have always avoided compounds/tarnish removers/polishes and paste and just let them "age naturally", so to speak. Rifle brass is a very different story and I treat those with loving care and respect.
So I thought it might be a good idea to post a thread so some of us could offer up some of the other things they do to clean brass effectively (or not) without a lot of hassle. I tried it in a bag in the dishwasher once, but I loaded them a little too soon and found some duds due to dampness. Further, I realized this was probably not very safe due to the possibility of lead contamination, so I stopped that practice right away......