My question is....Would a lubed wad over the ball be effective in preventing a chain-fire?--Patrice
IMO yes, if they fit snug enough to not move during firing.
That could depend on the size, thickness and composition of the wad and the lube.
They can be coated with a hard waxy lube.
There's fiber gasket wads that aren't lubed that are cut over size.
And there's over powder cards of various thicknesses that can be cut to fit very snug.
These Ox Yoke Revolver Wonder Seals are designed to go over the ball and they aren't even made from dense felt.
And dense felt is made in a variety of thicknesses that can be cut to be as snug as desired.
However a waxed wad or an over powder card could be placed under the ball with less risk of contaminating the powder compared to a wad that was saturated with a soft lube.