For .22 dry firing on a lot of my guns, I take a spent .22 case, snip off part of the rim with flush-cut diagonal cutters (not the only way to do this) and insert it in the chamber with the cut off part placed under where the extractor sits. This allows re-cocking for the next dry fire without having the case get extracted. Real convenient. Need I add that I cut off the part where the firing pin originally dented the rim?
I do this disunirregardless of whether the manufacturer says it's ok to dry fire or not.
Eventually the cushioning effect of the empty .22 rim decreases, so you take your trusty cleaning rod and push it out.
There are plastic dry-fire cases, but I've never found any to be satisfactory.
So, cheapskate that I am, I just cut off the rims of fired cases.
Cheapskate, 230RN