I talked to The Plumber as well and he said the 5.1-inch Schenkl was a beauty. He also said the putty job by the guy was excellent with good rifling, etc. and was on a number of shells. Let us know 24thMichigan when you get it but I bet that one on the right in your image is what they are calling putty as, at least to me, it seems to be expanded more than one would expect from a fired Hotchkiss. That would be some serious windage on the iron. Also of note though it is a fired projectile it is not as short as it should be when compared to the one to the left of it. But I hope I'm wrong.