Do you have a copy of the regs? If you don't, I would recommend that you get a hard copy for free from any sportings good store.
Pg. 90
http://files.dnr.state.mn.us/rlp/regulations/hunting/2007/full_regs.pdf
Quote:
Only open and “peep” type sights (including those with fiber optic material)
are legal during the muzzleloader deer season. Scopes, including
holographic or “red dot” scopes, are not legal for this season, except for
use of non-magnifying scopes by special permit for persons with medically
verified visual impairments.
A link with some more info you might be interested in.
http://www.dnr.state.mn.us/regulations/hunting/index.html
Also note, if you have a regular muzzleloading license, you can take a deer of either sex during the muzzleloader deer season. If you have one of the all season license, you can hunt muzzleloader season but can only tag a buck unless you applied in the lottery and was successful in being drawn for a antlerless tag.