A cartritge has to develope 500 ft lbs of energy at 100 yards. The 357 is out there also.
While I agree that the 357 magnum is not legal in Montana, the quoted is not the reason, there are loads that out of a carbine still have over 900 foot pounds at 100 yards.
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 25 of my guns are 45/70 govt, 357 mag, 22 or 12 ga... I believe in keeping it simple