I've dabbled in some round ball loads in 20 and 12, about to get more serious about loading slugs in a rifles H&R. It is chambered for 3" shells. So the question is; besuides the obvious power advantage it would give, which really doesn't matter, would there be an accuracy advantage to using 3" hulls so as to avoid the slug of ball have to jump a"free bore" before engaging the rifling?