For hiking and camping, I usually do 9mm (auto), .40 (auto) or .357mag (revolver). I live in Maryland. Most of my outdoors activities are in MD, VA, PA and WV. We are in the historic range for eastern cougars, but they have been killed off for some time now (though, it seems cougars/mountain lions, like coyotes are making a comeback and their range is increasing, so they may be back soon). They are a relatively thin skinned animal that weighs about the same as we do, so I'm pretty sure that a moderate power defensive cartridge with reasonable penetration will take care of it. Black bear are more likely to be scared of us and run, but if they don't, they don't usually get all that large around here. A 9mm or .40 from Buffalo Bore (not the usual defensive rounds) should do it, though I am far more likely to need to use a gun to defend myself from a human attacker than an attacking bear so I often use 9mm or .40 with defensive rounds when in the woods, and carry bear strength pepper spray in case I encounter a bear. That said, a woods gun is a good excuse for a revolver, and in the middle of nowhere I'm less likely to face a human attacker, so it is often an excuse for a revolver. My .357mag Colt King Cobra (new model) with a 3" barrel is most likely to come, followed by my .45LC S&W 625MG and .357mag S&W 65LS (the Colt is lighter and easier to carry while still packing 6 rounds of .357mag out of a 3" barrel, the 625MG is a bit heavy so it gets significantly less carry, the 65LS is in too nice condition to risk getting banged up so while I sometimes take it, it is far less than the other two). When I go far enough north to possibly encounter moose, then the 625MG is my choice. In a few years when I take a summer to do a cross country camping trip, I'll probably pick up a .44mag or a Ruger .45LC capable of taking "Ruger only" loads since that will put me in grizzly territory.