I have never "pre-cleaned". I just sort by caliber with a stacked tray system in a 5 gallon bucket. This process involves some jostling, shaking, and handling the empty cases that will often dislodge trash.
As for cleaning, I used to use dry media in a vibrating tumbler, then for a while...
Is the brass separated by caliber? If not already, do so before you try any sort of cleaning. 9mm cases stuck in 45acp cases can be frustrating! Is this a "pre-clean" you are trying to accomplish before a finale clean?
38 Colt , 38 Short Colt, 38 Long Colt, 38S&W Short, 38 S&W long, 38 Automatic , 38 Super Automatic, 38/200 Mk II. I am sure I missed a few.
Not a guessing game for people that want to keep their fingers attached to their hands.
Not a thing to be "pretty sure" about. I know a guy that lost fingers because he was "pretty sure" that old double barrel Damascus could handle modern shot-shells.
A good source for female self defense options / discussions can usually be found on "Cornered Cat".
https://www.corneredcat.com/
Looks like they have published a book now!