If you get a slug gun which is a rifled barrel then only use sabbot slugs because they are not rifled slugs. If you use rifled slugs in a rifled barrel then it will mess the rifle in your barrel up. If you buy a shotgun with a smooth bore then buy some rifled slugs and use a Mod choke tube. You can use buckshot in a smooth bore but not a rifled barrel. Last but not least, over and unders and side by sides are not good deer hunting guns. They are mainly for skeet shooting and bird hunting.