Sabots are indeed made for the rifled barrels.
I know guys who use the rifled slugs in them and just clean up the mess, but I just have to think there would be some accuracy issue with the twist rate, tewist dierection, or just plain tearing up of the outside of the slugs with two different rifleing trying to steer the same projectile.

Never tried it or compared myself sine the sabots shoot so darned good.