And, you can shoot rifled slugs in a rifled barrel just fine, too.
People have been doing it for many years.
Yes, but don't go out of your way to buy any for your smoothbore. If I want performance out of my rifled barrel, I will only shoot sabots. Or as they say in Spanish; "Sabotos" .....And, you can shoot rifled slugs in a rifled barrel just fine, too.
All shot guns with smooth bore have a choke designation even if it is "cylinder" choke or no constriction at all.(if you don't have a choke, then disregard)