My favorite 22lr Ammo for target shooting and even squirel hunting is CCI Standard velocity. It tends to be cleaner then many other brands and I find it to be as accurate as any other non-match ammo I have tried.
Now, I have and do use some of the Fedeal gold Metal match and Eley match ammo too but that is quite a bit more expensive and I goubt in a handgun you will gen enough extra accuracy that it is worth it. Out of my remington 541T-HB I can shoot under 1-inch groups (best was 0.7-inches) at 100-yards with some of that Eley ammo but I don't remember which. Squirels don't stand a prayer when I bring that gun/ammo combination out to play!