So I always thought the purpose of the "rifling" on a rifled slug was to impart a slight spin on the slug as it traveled through the barrel. After doing a little research I've found a good chunk of people think the rifling does nothing more than act as a swaging buffer so the slug fits the barrel as well as it can. I'm starting to lean more towards the swaging idea. Does the fact that the slug is heavy in front and light in the back give it its balance (much like a shuttlecock for example)? If the rifling is there for swaging why is it almost always twisted or angled? Thank you for your input.