Every established reloading information source I've ever read has said, loud and clear:
Never use powder which has no definite identity marked on the container.
Guess it could be argued that since these 24.3gr of powder were already loaded up, then the powder could simply be replaced and corked up with a newer, shiny bullet of the same weight as was previously extracted when the powder was dumped. But then, that argument leads to this point:
Every established reloading information source I've ever read has said, loud and clear:
Never shoot orphan (unidentified source; unknown reloading data) reloaded ammunition.
My recommendation to you is same as up above: Dump the Powder. (Sprinkled thinly in the garden. Excellent fertilizer. All that nitrogen.............)
Those twenty cartridges only contain a total of 0.07lb of powder, which is worth at the most, say..... $1.75. Not really worth messing with.
FWIW,