I doubt that I've shot more than a dozen or so fox squirrels with a .22 LR since I got my first 17HM2 in 2007. If there is a perfect fit of cartridge and game, I think that the 17HM2 and tree squirrels would be the poster child.
Stalk 'em, squeak at 'em, shot 'em in the head, and hope that you remember where they fell to Earth while you're waiting for the next one to offer a shot.
