I did some .30 rimfire reloading last fall. Completely obsolete stuff, so I made reloadable cartridges. Learned plenty about powder drop tubes, heeled bullets, and JPW as a bullet lube. .22 rimfire, like most of the obsolete stuff I load, is something I'd do just to say I can. ;-)
I know someone who tested using roll caps in spent .22 cases, he used a punch to flatten the bottom back down and put the caps in, forgot how he got it secure, may have just packed it with plenty of powder but he was able to get probably 70% of them to fire, not good enough percentage so he gave up. We both did "repriming" center fire cartridges with roll caps I could only get 2-3 out of 5 to fire, I didn't load the ammo just tested the primed shells, same concept, tap out the divit, put the cap in, put the little piece of metal back in and prime. They are called guerrilla primers and in a dire situation could work, but why horde roll caps when you can horde primers or more ammo. I do have a ton of roll caps and a tool for making percussion caps from soda cans though for my BP revolvers and they work great. Had a hard time finding caps for a while.
Doesn't seem to be very cost effective. We will keep reloading 30-06 and .223 and keep stocking .22 lr deep.
