In the mountains, weight adds up fast.
I always have a 15 oz. S&W Airweight .38 snubbie in my pocket regardless that's concealed.
Other than that, it depends on where I am and what I expect to be doing. I'll open carry where legal, and carry concealed where it's not legal to OC.
My primary firearm will be fairly light, but "powerful" for its size/weight. The guns may include:
Kimber Ultra CDP (aluminum-framed, 3" barreled "Officer's size" 1911 in .45ACP) + 2 extra magazines, or
S&W Model 19, 2 1/2" barrel in .357 in a Bianchi thumb break belt holster + one speedloader, or
S&W Model 65, 3" barrel in .357 in a belt slide holster + one speedloader
Less strenuous terrain, a 3 1/4" barrel custom S&W 25-2 revolver (.45ACP), loaded with hot .45 Auto Rim cartridges, with a pair of .45ACP moonclips for reloads. I carry it either in a cross-draw belt holster or a shoulder rig.
They sell pepper spray, or OC, for bears that works great in repelling them, I've read. I'm more worried about 2-legged predators and/or wild hogs, wild dogs and coyotes . . . and in carrying more weight than I want to pack in!!!
Heck, in small game hunting season in my neck of the woods, my main carry firearm is generally a Ruger MkII Target Model .22LR automatic, carried in an Uncle Mikes belt and holster, topped with a 2nd generation Bushnell Holosight.