MCL 750.222 Yes, provided the rifle or shotgun is 30 inches or less in overall length with the stock collapsed/folded but at least 26 inches and the barrel length is at least 16 inches and 18 inches respectively. Attorney Generals opinion #6280: if the firearm is less than 26 inches in overall length or the barrel is less than 16 or 18 inches respectively, the firearm is considered a short-barreled rifle or shotgun and is illegal to possess. MCL 750.224d There is an exception for short-barreled shotguns and short-barreled rifles which the Federal Bureau of Alcohol, Tobacco and Firearms has found to be a curio, relic, antique, museum piece, or collectors item not likely to be used as a weapon.
Rifles, and shotguns which have an overall length less than 30 inches, but more than 26 inches are considered pistols in Michigan, if you have a folding, or telescoping stock the measurement is taken with the stock folded, or collapsed.
i would asume it would be considered a pistol. not sure if it becomes a short barreled weapon or not. i will wait for others to chime in who know the laws on SBR but thats what i could find in a basic google search of michigans sbr laws