Do yourself a favor and order some JSB Diablo Exacts in the 18.13gr size. They're by far the best .22 cal pellets I've used on squirrels, rabbits, and other vermin. The Predator PolyMags work well too, as they are simply JSBs with the polymer tip, and they can be devastating on body shots, but they're not quite as accurate in the 30-50 yard range.
Also... squirrels are pretty damn tough when you're talking about pellet gun quarry. Shot placement is paramount, and small misses often lead to bad results.
