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Ref: tumbling loaded ammo

I read a very good writeup a few years back about tumbling loaded ammo. A guy assembled a batch of match prepped ammo and them proceeded to chrono them 10 rounds at a time after tumbling something like 0, 1/2, 1, 2, 4, 8 16... hours. He found only a couple of % change in velocity after an obnoxiously long tumbling time and nothing after over 8 hours that was outside experimental error. Some day I'll repeat that experiment with pistol ammo to see if it follows the trend...right after about 10+ other similar experiments I want to run.

A short tumble to remove lube shouldn't hurt anything...but I still wouldn't leave them in overnight.

Pistol and rifle get different answers...

Pistol: Tumble and then size/deprime, as it knocks out the bit of polishing media form the flash hole and you should be using carbide dies without any lube. Lubing pistol brass adds way more time than the cost of carbide (or nitride from Hornady) is worth IMHO.

Rifle: tumble twice, once short to remove any grit and thereby prevent scratched/ruined dies, then lube and size normally. I then wipe down to get the bulk of lube off and tumble until shiny. I'll then go back with a jewelers flat screwdriver and clean the primer pocket and punch out any stuck media from the flash hole.

Alt rifle: If you trust your wipe down to get the lube off your brass, you can do a full tumble once before depriming/sizing, but I don't. YMMV.