body shots the 17hmr will destroy a small varmint. heads shots will work fine. if you worry about this you could always step down the 17m2. it wont have as much explosive power as the 17hmr . if you go with the 17hmr the cii hollow poitns dont do nearly as much damage to game as teh ballistic tips. i owna marlin 917vs and couldnt be happeir my cusion owna cz american and love it. they are both very accurate firearms. for more info on 17hmr and those gun go to www.rimfirecentral.com