Try a better idea submitted by another member here several weeks ago.
Instead of using overpowder wads, use over shot cards(wafers). To fit them through the choke, just turn them sideways. You can put a small air hole in the outer portion of the wafer to let air escape, or someone else cut a slit in the wafer from the edge to the center. Use more than one wafer, and just turn them so no two holes or slits are aligned. The one suggestion was to use 5 wafers under the shot to seal gases, and then two wafers on top of the shot to hold the loads in place.
With the slits, the idea was to use 3 or 4( or more) wafers over the powder, and then a couple over the top of the shot. The idea of using wafers instead of Overshot wads was they were much lighter, would not follow the shot, and break holes in the pattern, and that in the field you only had to carry one kind of " wad " for all purposes, and not two or three different ones.
Sounds like a good idea even on the range. I believe he lubed his gun by putting a ball of lube on the underside of one of the wafers in the stack that was between the powder and shot. You could also carry lubed patches in a can, and run one down the barrel after loading the gun.
I thought the two suggestions were the best way to deal with choke tubes, and fixed choked barrels. Anything to keep from having to unscrew and screw back in those choke tubes in the field, or at the range! :hmm: :bow: