What gun do you squirrel-hunt with?
I always use a .22 LR. My first time out as a kid - .410, but graduated up to using sights rather quickly.
Also, If I end up buying a .223 for coyotes, and I have now luck on a hunt, I would probably try to go home with at least a squirrel. I guess I better make sure it's a head shot with that .223, eh?