In thinking this topic over, I have to think of the 12 and 10 bore paradox rifles built in the late 1800's. This rifles were basically shotguns with rifled chokes. They were used with both shot and slug, but mostly slug. Many of them had up to .022" rifling depth over the last 3" of the muzzle, with very wide lands. The ball or generally VERY heavy slug, which was bore or slightly larger than bore size when started, traveled down the tube to hit the choke at the end of the bore, engaged and 'took' the rifling, was spun to stability and shot with fair accuracy up to 200yards as well.
To me, a round ball if patched or bare, that is loaded through the choke at the muzzle, must be OK to exit that same muzzle.
Perhaps Colerain has had trouble with their choked barrels and solid shot. This must then declare their barrel materials to be inferior to the English damascus barrels of the late 1800's.
This is possible.