I will tell you from experience that a .22 cartridge belt is about the most useless thing you'll ever buy.
It will hold probably fifty cartridges. Think how long it will take to fill fifty cartridge loops, and how quick you can fire fifty cartridges.
It's like filling up a teen-age boy.
I have never had a .22 rim fire cartridge belt, but came to the same conclusion when filling the loops on a western rig for a S.A. .44 Magnum...There has to be a better way. Another consideration is that .22 rim fire are externally lubed and the lube could wear-off very easily (you can scrape it off with your finger nail), if the .22 rounds were in the loops while you sat in a chair, rode in a car, etc. In other words, belt loops do not provide any protection for the cartridges.