RE: Pistol Caliber for Deer
Look at your hunting regs first. Some states regulate handguns based on caliber, some regulate based on muzzle velocityetc.
If I were you and you really want to pistol hunt go with the 44 mag as stated earlier and shoot close 75 yds or less. I am only comfortable with my 44 out to about 30-40 yds but thats me.