I like my reloads to look as good or better than factory, so ...
First I deprime (not size).
Then ultrasonic cleaner: Suspend 2 Liter Kimax beaker, filled to 1 liter with ~2 tblsp of citric acid powder, 4-5 drops of dish soap, & water. Insert cases (~75 45 ACP’s or ~30 7MM Rem Mag’s). Run Ultrasonic for 7-8 min. strain & dump cases into another beaker of hot water w/~1tbsp baking soda. Agitate & let soak ~5 min. Drain & dump into beaker of distilled or R.O. water let soak for ~2 min. Strain & let dry. With pistol cases, I usually have more to process, so I dump the citric acid solution after ~5 uses, or when the primer pockets start to not look absolutely clean, whichever comes 1st. I have a 6 liter ultrasonic cleaner, so I can process two beakers at a time.
Then 1-2 hrs. in vibratory tumbler w/ corncob & ½ capful Nufinish & ½ capful mineral spirits - plus2-3 paper towels, cut into ~1.5" squares (or a couple of used dryer sheets - which I never seem to have). Actually, I only add Nufinish every 4th or 5th load, but mineral spirits every load.
The ultrasonic gets them squeaky clean, inside & out. Tumbling adds shine & the Nufinish/mineral spirits keep them from being too dry, as the ultrasonic leaves them completely clean, but hard to size/seat.
When done, the brass looks better than new – but of course it’s not.
I don't worry about any media which might be lodged in the flash hole - the primer punch knocks 'em out when I resize.
Citric acid powder does’nt have a yucky smell like vinegar does & when neutralized w/baking soda doesn’t seem to have any bad effects on the brass. I wouldn’t recommend leaving them in any longer or heating the cleaning solution, though – it seems to be a pretty aggressive cleaner. I have tried vinegar instead of citric acid (vinegar/water ~50/50, but I think the citric acid mix works better & is way cheaper. The citric acid is very cheap if bought in bulk(~$6 for 2 lbs). It’s used in baking & soap making, easy to find.
Just remember it IS ACID. Be careful not to spill it & clean everything that might have come in contact with it. Also, store it carefully. It will corrode steel very effectively.
YMMV