I would have to say the 30-30 and the 357 magnum (from a rifle)
In the past the 30-30 was used to kill all kinds of tough creatures this side of the pond and worked just fine. The animals have not evolved armor over the last 100 years but many people will tell you the 30-30 is not up to the task.
The 357 magnum from a Carbine barrel is much more powerful than from a handgun. There are loads that will push a 158 grain bullet 2200 FPS (again from a rifle). While it is no Dangerous Game round, it is much more potent than most people give it credit for.
Shot placement is everything! I would rather take a round of 50BMG to the foot than a 22short to the base of the skull.
all 26 of my guns are 45/70 govt, 357 mag, 22 or 12 ga... I believe in keeping it simple. Wish my wife did as well...