ultrasonic works for brass cleaning, however the brass comes out dull.
I am done buying gimmicky ultrasonic solutions...they all work the same...not very well.
My ultrasonic solution is lemishine + palmolive dish soap (the green one that's a degreaser)...this works better than all the solutions i've tried.
Even still, case necks are still dirty, but primer pockets are clean.
Case cleaning for me is as follows:
1. deprime/resize spent cases
2. ultrasonically clean them w lemishine + palmolive dish soap (at least 5 30minute sessions in boiling hot water)
3. tumble the brass for 12hrs -18hrs (tumbling alone does no clean the primer pockets)
Cases come out shinier than new brass...