What exactly are your rules for Colorado? No sabots correct?
Depends on whether you are hunting in the Muzzleloader season, or the general rifle season. Also depends on the size of the game you are hunting for caliber.
During Muzzleloader season, for elk and moose, it is .50 cal minimum full bore conical. For deer, bear, sheep, antelope, etc, the minimum is .40 caliber full bore.
This will be easier and more accurate.
Click to expand. Colorado.