Thank you, gentlemen. Your comments are helpful. If you use any internet search engine like duckduckgo.com, google etc the best "greased cloth" results you will get are a few photos of old Purdey and Lancaster gun case labels, where the millboard card wad and the "greased cloth" are explicitly mentioned. While I thought that lubed felt wads would be the equivalent of greased cloth, my guns get terrible accuracy with the felts. So scratch that idea. Whatever it was, it was a known thing and it worked well. Those people lucky enough to have pulled apart original BPE rounds seem to have dismissed the two wads found inside, or not really analyzed them. Recently I ordered and used actual millboard in lieu of the regular vegetable fiber wads most of us use. Millboard in 1888 was used for bookmaking and also as the over-powder wad in black powder cartridges. It is much stiffer than the vegetable fiber wads, though bendy enough to not act as an obstruction in the barrel. As the felt wads have always let me down, I have gone back to using Dacron pillow stuffing over the millboard, because something must take up the air space in the shell, and unlike the felt wads, the Dacron rounds are really high performers. Now I wonder if I dipped the Dacron in some sort of natural grease, would it in effect basically amount to the "greased cloth" of yore...By the way, in my flintlock I have been using bear grease on the round ball patches, and it is fantastic. Best lubricant I have ever used.
