Slim, where does the .44-40 fit into there. Its my understanding that it was the fore-runner of the .44 special...which is one of my personal favorite pistola rounds.
The .44-40 is of a separate family tree, also called the .44 WCF (Winchester Center fire) with is (IIRC) a .45 Colt casing necked down to .44. The Specials are all straight cases.