For thu hunting you now describe, if it were me, I'd bring along my Marlin 1895 SS in 45/70. I have a peep sight on it now, and I wouldn't hesititate to shoot out to 100 yds. It goes "boom", not "crack". Puts a whallop on deer too. If you want deer to drop fast, shoot to break the offside shoulder, or use the high shoulder shot. Be sure to use a bullet that is sturdy enough. The Hornady 350 gr Leverevolution is just the ticket. The 35 Remington would probably work as well, as would a 444 Marlin.