Instead of using dawn for SS pin tumbling, use any brand of car "wash&wax" liquid car wash soap.
It contains some wax, so that brass retains a thin wax coating even after a good rinse.
You can barely feel it on the dried brass, but it prevents any tarnishing for a long time (about a yr in my location)
and it makes sizing use a lot less effort.

I use armour all brand but others say they get the same results with other brands.