Once you have sorted out the likely contenders, its a good idea to put a box of each through it to see if the groups tighten up. I was testing a few years ago with my semi for a better round. As I put a box of rws hp through it you could see the groups visibly shrink as I emptied a box through it.
If you look over the forums historically, most cz's .22lrs like either eley or Winchester.