I use a 30/30 Marlin RC for all Big game including bear, caribou, moose, elk, deer,...
I use the same gun for coyotes, jackrabbits, whatever...
That said I have used many rifles, and now and then use something different.
Sako Battue 7mm-08,..(this years bear)
45/70, 450 Marlin, .35 Remington. 223 wssm, 220 swift,.8mm Rem mag,
CZ 55o Kev and Lam in 22 250, ...
For small game i use a .22 Marlin Golden Mountie, SxS 16 gauge,..
For Waterfowl it used to always be my Beretta... but as of late it has been multiple shotguns,..mainly semi autos
If I had my .22, my 30-30 and my Beretta I would satisfied 99% of the time for most of my hunting