Ticking, denim, pocket drill, linen, lighter canvases. Those are shooting patch materials.
I have used denim from .O19" to .034" thick with the best effect.
Linens and pocket drill thick enough to be used without having to wipe the bore while shooting, are hard to find.
Ticking ie: heavy ticking running .021" to .0235" thick make excellent shooting patches.
The most accurate loads I have developed use 10, 12 and 14oz. denims. In the U. States, Joanne's Fabrics Carrie's denims in ounce weights.
I measure 8oz. Denim at .018", 10oz. at .022", 12oz. at .030" and 12oz. at .034".
These 2 heavier denims shoot best my .69, having .012" deep rifling with the .682" pure lead ball, and with a hardened ball of .677" using the thicker patch.
Having at ANY time, to wipe during shooting 5 or even 10 shot groups, shows your bore condition is changing, shot to shot. If this is happening, pressure and velocity is also changing shot to shot, therefore you are not getting the accuracy your gun is capable of.
We shoot for an entire day without having to wipe at any time. That may be 30 shots or 100. The bore's condition does not change.