Lead ?

[J.B.]

Just be sure you're looking at the lead and not the chamber end. The end of a modern cut chamber end is fairly easy to pick with the eye... the lead, not so much. That photo Kurt posted with the two 44/90 chambers shows the current 'standard' Shiloh 44/90 chamber with the 45 degree chamber end... there is still a lead there, possibly 2-3 degrees and of short duration..but it is there. The early guns, mostly used with paper patch, didnt seem to have the abrupt chamber ends that we consider standard today. The chamber mouth...appears to give way to the lead..and then the rifling in a smooth, constant transition. This is evident in the castings from the originals. Or that is how it appears to me.

J.B.