LNGBOWFLYER
Sorry, I didn't see that no one answered your post. From the Utah Game Regs Book, it doesn't say they aren't allowed (see bullet point 7), so I surmise they are allowed. Anyone else know for sure?
Muzzleloaders
Utah Code § 23-20-3 and Utah Admin. Rule R657-5-10
Muzzleloaders may be used during any big
game hunt—except the archery hunt. To hunt
big game with a muzzleloader, your muzzleloader
must meet all of the following requirements:
• It can be loaded only from the muzzle.
• It must have open sights, peep sights or a
fixed non-magnifying 1x scope.
• It can have only one barrel, and the barrel
must be at least 18 inches long.
• It cannot be capable of firing more than
once without being reloaded.
• The powder and bullet—or powder, sabot
and bullet—cannot be bonded together as
one unit for loading.
• It must be loaded with black powder or a
black powder substitute. The black powder
or black power substitute cannot contain
smokeless powder, but may contain some
nitrocellulose.
• To hunt big game, you must use a lead or
expanding bullet or projectile that’s at least
40 caliber in size.
• If you’re hunting deer or pronghorn, your
bullet must be 130 grains or heavier, or your
sabot must be 170 grains or heavier.
• If you’re hunting elk, moose, bison, bighorn
sheep or Rocky Mountain goats, you must
use a 210-grain or heavier bullet, or a sabot
bullet that’s at least 240 grains.