for good old rabbit and squirrel hunting the tried and true .22LR is cheap and worthy as anything you can use. To it's range which I consider 35 yards it's extremely accurate and powerful enough to do small game very well.

I have a Marlin 60 semi auto that's very accurate and reliable but the 10/22 crowd is very high on that gun as well. Look the field over....there's some very fine bolts, autos, as well as leveractions and pumps and the used racks present a plethora of bargains as well.