You are right I thought the width would have been 1/2 inch also from the illustration. The band material is .025 thick and about as springy as feeler gauge stock. I was afraid to bend it more thinking I would get a permanent deformation. The 2 ends are bent out on purpose and the getting the width down to 1/2 may work correctly with those bends. I still have all the tools in the lathe so I can do a couple more. I will try one at .6 and .5 inches. If the .6 works without feeling like I am permanently deforming the band then I will try the .5 inch.
Also need to rethink what bottom of the stock will need, a 7/8 inch washer there would look terrible even if it was coned to sort of match the contour of the stock.
Brownels has a couple of "barrel bands " in their catalog. Maybe they have an online photo. I can tell nothing from their print illustration.
The attached photo shows the top of the band, nothing moved since the first photo. Matches the barrel radius pretty well at 12.5 inches.

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