These guns, all direct copies of 19th century pieces, were designed by their inventors to use powder and ball, or conicals, not, as far as I can find, wads or fillers.
I've tested all my Uberti Colts with full loads, no lube or wads, and they will function thru cylinder load after cylinder load, eight in my case. Accuracy suffers and in the end cylinder rotation is difficult, but on an 12X18 target 12 yards, the 48th shot was still in the kill zone.
Powder and ball, and in the interest of keeping fouling to manageable levels a dab of lube, liquid or solid over the chamber mouth. No fillers, no wads necessary, not saying they don't have a function, the filler, IMO is needed only in extreme reduced powder charges, they are just not necessary to an average shooter for accurate fun shooting.
A handy reference to determine if enough lube is used is to examine the muzzle after six shots. A slight ring of lube should be noticeable around the muzzle.
As already mention, these are time tested guns of a simple design requiring simple components, don't over think it.