I bounced a .45 ACP hollow point round of a beaver head from about 30' once while we were fishing from a bank. I was sure I hit the critter but it didn't float. The beaver re-surfaced about 15 minutes after the event with a bald spot between it's ears. It was decided that the nuisance creature earned another day. We argued the rest of the day about whether the bullet was from a bounce or a grazing shot.
Pesky beavers!