No, I know guys that use them in a 1 and 35 twist muzzle loader. I don't think the actual sabot makes that much of a difference. It's just a jacket that breaks away, the spin will be the same. However the velocity will be higher out of a shotgun most likely which would make a difference.

The problem with muzzle loaders is the barrel diameters are not consistant. Just because you have a .50 cal rifle does not mean they all have the same inside diameter. So you sometimes have to experiment with different sabot thicknesses to see what your particular rifle likes. My buddy has a night wolverine and it does not like remingtons sabots at all. They are too big for his barrel. However they fit pretty nice in my remington 700. So I would guess my barrel is slightly larger than his is.

My ML prefers the Precision Rifle QT bullets actually. Now that is something I would like to see in a shotgun slug offering. Maybe a 400-450 grn QT bullet.

The only way to know is try. Some like the barnes expanders by federal out their shotguns. Mine hates them. Won't even shoot 2 foot groups consistantly at 100 yards.

Paul