An effective rimfire mix can be made by gently removing and crushing the tips of "strike anywhere" matches, then adding a little hot water to make a slurry thin enough so that you can drip a bit into the bottom of the case, then spin the case on an appropriate sized dowel or drill rod to centrifuge the priming slurry out into the rim.
Both the settlers and Indians knew how to do this 100+ years ago... Lots of rimfire cases found on archaelogical digs in the West have 2, 3 or more firing pin marks on them. Even given that some of the early rimfire guns had double firing pins to increase reliability with the somewhat crude priming technology of the times, we KNOW they frequently reloaded these cases.