Reading a period (~1875) sea story novel, there's a passage describing the powder crew on a US frigate. Nailess felt shoes, garb with no buttons, etc., and they'd march in to the copper lined magazine turn the powder kegs every so often to help keep the powder from separating.
But, this unfortunate occurrence makes the passage a description of busy work, or an exercise in safety handling the stuff in such. (Probably beat the grunt work on a wooden ship of the era)
They did that not to keep the powder from separating, but to keep it from bunching up in into a clogged lump (which would burn too slowly or not at all) in the humid, salty, air at sea.