So, what partly brought this thread about?
http://www.oldammo.com/january12.htm .
This is a good read. Especially for those into cartridge history or slug users. The first slug I used was the BRI sabot out of an iron sighted smoothbore Mossberg 500 during the mid 80's. A rifled barrel came later. These still give the best performance for me so far of the slugs I've tested.