Is there any reference to how copper driving bands are fitted to large calibre shells/ projectiles. Is the band crimped or swaged in place and machined to size or does the crimp or swaging process form the finished driving band.
The book by Pratt “Manufacture of Artillery Ammunition”, published in 1917 could have this information.
I think it is available online in the Internet.
There is several ways and one need to observe when and by whom it was made.
Swaging an oversized ring into a knurled groove and lathe-turning into shape is the most common but in the early days also a copper band was hammered into a groove and the ends were worked over to make an exact fit.
Since at least WW2 (Germany) build-up welding is known and used by some manufacturers (most prominent are the Russians with 30mm projectiles).
Plus many experiments were made as it also often involved testing of replacement materials since copper was/is quite expensive and in war times always in short supply (to one more to another less but never being wasted).