When I was in college (Colorado) we used to go to the local dump (long before land fills) and shoot rats with .22 longs and shorts. Hard to do. Then we tried .38 and .45 hand guns. A bit better. Finally the 12 gauge really did the trick.
Back in the 50s my buddy and I were shooting rats at the dump and we both came close to dying that night. He because a rat ran up his pant leg and me because I was ROTGLMAO!!!