Frank, Thank you very kindly for the gracious offer of your tools, very unexpected and generous. I feel that this is something I had better have done for me by someone who has a clue (not me) what they are doing in metalwork.
Dominic is right on the mark as usual, 1/8" thickness liner, no sign of how it's secured that I recognize. Since this is intended for someone else to use, I want it to be safe as well as fun to use.
This is from the SBR Catalog 2006 - 2007:
"All barrels are poured solid and drilled. With the exception of mortars, iron barrels are fitted with steel bore sleeves breeched with welded steel plugs. Wall thickness of the sleeve up through 1-¼" bores is 1/8". From 1-½" bores up through 2-¾", the wall thickness is 1/4". Wall thickness of the 3" bores is 3/8", and over that, 7/16". For sleeving, bores are drilled and inspected inside, and then fitted with seemless steel tubing, bonded in place. Mortars are properly chambered."
"The result is the excellent concentricity allowed by drilling, step-by-step observation of the process, an absence of core pins buried in or sticking through the casting, the reinforcement of sleeving, and a straight and mirror-smooth bore undisturbed by heat distortion or other factors. Superior appearance of castings is another benefit of pouring solid, since no air or other matter is trapped in the center of the molds to act unfavorably on the metal during pouring."
I don't usually say anything till I have it in hand, but it recently came about that one of these scale IX-inch Dahlgrens became available to me, so the price has been agreed to, and the deal has been cast; now all that's needed is a little faith that in a week or so I'll be able to start measuring the barrel for the wooden Marsilly carriage I intend to mount it on. One of the things that I plan on doing is putting a bouche in the 'side' vent so that no water seeps in between the steel/iron surfaces.
