Here are the MN rules for hunting big game.
http://www.dnr.state.mn.us/regulations/hunting/legalcartridges.html
The 50AE is legal, as it is grandfathered in via over all cartridge length. (just as the 10mm is)
Therefore, if the 50AE is, so is the 50 Beowulf.
The safe way to think about it is if the bullet has a greater diameter than .240, a cartridge lenght longer than 1.285", and a KE at the muzzle of more than 1000ft-lbs.
The 357magnum is one of the "smallest" rounds to hunt with from a handgun.
the 25-20 is the wimpiest rifle cartridge on the list. (which makes a 72gr .223 round look like a 308 by comparison...)
FYI: I base my 25-20 comments on the fact that its only a 75gr cast lead bullet and only goes 1700fps...my Rossi 92 with handloaded 357 magnums does that with bullets weighing 2x as much!!!
Funny thing is, the 50BMG is legal in MN, but not the 460 Rowland.
In ND, the 460 Rowland is legal, but, the 50BMG is not.
Go figure...
[Yours truely is going hunting with either his 38-55 Winchester or 30-30 Marlin]