The best hunting rifle would would have to take into consideration the intended game, possible threats encountered (such as perhaps encountering feral hogs while hunting rabbits), the average distances of targets in the terrain that you are in,, etc.
For me, I mainly use a pre '64 model 70 Winchester in .270 cal with a Leupold Vari-X III 2.5-8x scope.
The caliber is flat shooting over long distances, will shoot from a very light projectile to one big enough for an elk, (marginal on a bear), the scope magnification is enough for any long shot in Michigan, bolt action is the most reliable.