Tony, When i got my P22 i checked over at
http://www.rimfirecentral.com and read through quite a few posts. Personally, i've fired around 1000 rounds of CCI MiniMags with 0 problems. After switching rounds to Remington Gold Bullets (RGBs) i had a few problems. Obviously MiniMags are a bit on the expensive side, but they operate flawlessly (at least for me). What year was your P22 made? This also has something to do with the operation of the pistol. Mine is an 06 model (AG) on the barrel-AF is 05, AE is 04, and so on.. Hopefully you enjoyed your shooting and decide that the pistol is a keeper. It's definitely a fun little plinker.
Mike