Now I know that muzzle loaders don't have a lot in common but I used the T/C Natural Lube (Bore Butter) in my muzzle loading rifles right up until the time I switched away from black powder and Pyrodex and went to the Buckhorn 209 substitute. It was almost like smokeless powder and had to be cleaned with Hoppe's or some bore cleaner made for smokeless powders. I even used it in my black powder shotgun when I dove or turkey hunted with it. Before I started using it on the ML shotgun, every time I fired it with a regular shotgun wad, it would leave a skim of melted wad smeared inside the shotgun barrel. When you reloaded it the melted plastic would push back to the bottom of the barrel. After enough shots it would actually form a plastic donut in the bottom of the barrel that had to be removed with a stuck patch remover. When I started using the Natural Lube it no longer left the melted plastic in the bore.
It may not do a bit of good on turkey gun patterns but it should at least be worth a try. Nothing to loose by trying it. I'll let you know what happens.