http://www.natchezss.com/product.cfm...&prodID=HO6752 a little off topic but i wonder what these are like?

They are basically a plastic sabot that you out a roundball into. There are some people that have shot them and had pretty good results actually. I too intend to experiment with basically the same thing. I want to put a .58 caliber ball into a 20 gauge shotgun wad with an over the shot card on that. Then shoot that out of my smoothbore. I am hoping that it will act like a shotgun of sorts and give good accuracy to perhaps (could I be so lucky) 75 yards.

Yep...That's exactly what happened...

Rifles came to the Colonies via the German speaking immigrants...They were rifling barrels by the mid 1500s...This practice was less common in England and France...In the early and mid 1700 German immigration skyrocketed...They settled from Pennsylvania and down here into NC...
The early rifles that the German gunsmiths made evolved into the "Kentucky" or "Pennsylvania" rifle...I actually prefer "Early American Long Rifle"....The Germans cut the rifling into the barrel, one groove at a time, usually an all day operation...The "best" twists are about...1-48 for a .40
1-66 for a .45 and .50 and 1-72 for a .54...These are typical twists for the guys that actually make these barrels specifically for round ball guns...

These early arms were meant for hunting...They were very expensive to make, but they were the type arm that Daniel Boone brought with him when his family moved to NC in 1750, and the type he carried to Kentucky and the type David Crockett took to Texas...

The "Mini" was developed just before the Civil War...It was used in the rifled muskets used in that conflict...So the rifling had to be made more shallow and faster to stabilize...

Of course the plastic sabot was developed in the mid 1980s...And it all went to #ell in a hand basket after that....

Sorry...couldn't resist....