I killed a medium sized one when I was 19 with a 357 magnum carbine 16.25 inch barrel. A 308 is fine
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 23 of my guns are 45/70 govt 357 mag, 22 or 12 ga... I believe in keeping it simple