[Eye of Unk]

I remember a documentary of how the Brown Bess muskets were made, essentially wrapping flat steel around a dowel.
And a shotgun can be made damascus style with a higher grade of wire wrapped around the right size rod and either brazed or hard soldered. Or to just get a chrome-moly tube say from a roll bar.

[NVDave]

Want to see a fascinating movie about making damascus barrels?

Here:

http://damascus-barrels.com/Movie.html

Saw this in a class on restoring damascus shotgun barrels last summer. The level of work that could be accomplished by some of the barrel houses around Liege, Belgium, with nothing but manual labor and forges is amazing.