[ithacaartist]

Oxy-acetylene/propane will give plenty of heat to do the job; in a pinch, one can use two propane bottle torches. Sweating is good, but I think unnecessary, in that even if only the extremities of the joint are solid it would be plenty to hold the assembly in perpetuity.

I once hired out to one of those places around here that manufactures turbine blades. The particular order was too much for their in house welder, and I was taken on for a couple weeks. We used an RF generator to heat the materials between the tubes of its loop. We were silver soldering Stellite (an alloy that resists erosion from low pressure steam) strips into pockets milled on the blades' leading edges.

All parts had a final cleanse in alcohol; then a coat of paste flux, a strip of flat silver alloy clamped in between components, then turn on the juice/heat. An optical temp sensor helped us prevent over-temp. A bit of art work was involved because the heated piece had a significantly different shape than when cold. Our work was good enough to pass X-ray inspection at an acceptable rate, so I'm confident that if it can be done to a long set of dissimilar metals that changed shape that much when heated, not many would have problems doing such a straightforward chore as a barrel band. As an old timer at a scrap yard I worked in WAY back in the day, "Go right at it just like you knew what you was doin'!"