I cut a 410 case down for a powder measure as the full power load and most accurate ball load is a bit much for squirrel. It's about 25grn.
Then a lubed felt wad cut from an old hat and then a thin patched .440".
It's not the most accurate with that load but ok close up, to be honest shot at these distance is better!
The full power ball load is minute of rabbit head to 40+ yards (from a smooth bore)!
It's also very good with two balls.
U.