I used my .22 LR for years before upgrading to a 22-250. At 50 yards or less I could consistantly hit them in the head. 40 gr. CCI mini mags and 32 Gr. CCI Stingers work well. Shots in one ear and out the other are the way to go...I always aim for the ear. I could hit them at 75 yards, but with not as much consistancy. Let's just say I prefer the .22-250.