It is what it is. Any .22 centerfire or larger is legal big game. For that matter, you could use the .220 swift or a .22 hornet if you wanted to.
Chunkychuck wrote:http://files.dnr.state.mn.us/rlp/regulations/hunting/2011/full_regs.pdf
LEGAL FIREARMS (Includes handguns) FOR BIG GAME
• It is at least .220 caliber and has center fire ignition;
• It is loaded only with single projectile ammunition;
• The projectile used has a soft point or is an expanding bullet type;*
• The muzzleloader (long gun or handgun) used cannot be loaded at the
breech (muzzleloading revolvers are not legal for taking big game);
• The smooth-bore muzzleloader used is at least .45 caliber and
• The rifled muzzleloader used is at least .40 caliber;
• Muzzleloaders with scopes are legal during the regular firearms deer
seasons, but are not allowed during the muzzleloader season except by
special permit for hunters with a medically certified visual impairment.
Applications are available from the DNR Info Center, see page 125.
Other Restrictions
• No person may discharge a firearm or an arrow from a bow on, over,
across, or within the right-of-way of an improved public highway
(including but not limited to federal, state, county, and township
roadways) at a big game animal or a decoy of a big game animal that
has been set out by a licensed peace officer.
• A person may not use a dog or horse to take big game.
This is all I can find