I use a buffer between the patched ball and the powder charge in any muzzleloading gun. The reason is to prevent the patch lubricant from fouling the powder.
: In my rifles and smoothbores, there is no increase in velocity with using a wad (card, fibre or cloth) between the powder and patched ball as there is no blow-by on my tight fitting ball/patch combinations. Some othe rcombinations may show the increase. If that is the situation, perhaps a reasessment of the combination is in order.
: When confronted with this lack of vel. increase with a wad by an NAPR member at a shoot, Fadala chrono'd the fellow's tight fitting load and found that putting a wad between the ball and powder didn't increase his velocity as it did in Fadala's own rifle. When I repeated the test for myself, back in the 80's, I found the same thing - no change in velocity with or without the light Ox-yoke wad. The wad does, however, allow the charge to remain non-effected for a period of time, as in the entire season if need be. Personally, I'd discharge, clean and re-load at least every month. The longest I have gone is 2 months, then targeting the shot, obtained a centre hit. I was satisfied with the results. A card, as in tablet backing, or thicker as in cut from a monopoly board at .1" is very good. OxYoke wads increse the cost of shooting, and aren't necessary, as a card wad works just fine.