Great thread.

This short vid here shows the challenges and failures and successes w/ RB's in smooth and rifle tubes.

https://www.youtube.com/watch?v=UnQHEZ_w0Fc

By the way, Wade here has done some absolutely phenomenal works w/ buckshot. I found his vids some years ago and correspond with him from time to time. Great guy. Really amazing stuff & using his principles I've been able to duplicate his performance. He's spent a lot less time working on RB loads and slugs and even there has done some great work.