For those that use or want to use a Muzzleloader in Rifle Elk Season, the rules are exactly what's in the regulations book. A 50 caliber ML must use a bullet that weighs 170grns or larger. If you use a Muzzleloader that is bigger then a 50cal you must use a bullet that weights 210grns or heavier.

For example, I will be using a 50cal Muzzleloader this fall Elk Rifle season using a 250grn .452 bullet in a 50cal sabot. Just like I have the two other years I was out there. And all my equipment was checked at camp both times I shot Bull Elk by the Game officers.

After talking with Bob Thompson today, he assured me no rule changes for the 2015 Elk Rifle season.

On another note, talking about the XP bullets by Lehigh defense. As it clearly states in the Colorado regulations book, you cannot use a NON EXPANDING BULLET. So those bullets are not aloud to be used in Colorado Elk hunting during rifle season.

All above information is about Colorado Elk Rifle season. I have no reason to worry about or talk about any other seasons in Colorado. But the book clearly spells out other seasons as well.