good catch Capefearfly... that 7.62X39 with a 125gr. SP inside 100 yds. should be OK.
serious though, some of those dudes seem to approaching 4#. I was concerned a few times when they come down the same tree your sitting in or the branch next to ya trying to figure you out.
side note : boil the quarters + loins/rump for about 15 min. then pick clean... make soup similar to chix soup and put that squirrel meat in there.