From the 2009 Utah Big Game Guidebook: "Your ML must meet all of the following requirements: It can only be loaded 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 powder substitute cannot contain nitrocellulose-based smokeless powder. 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 prongbhorn, your bullet--including your sabot--must be 170 grain or heavier in weight. 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."
