That is a beautiful rifle, and the sort of restoration job it deserves. It annoys me when we see rarer firearms than a Nimschke Ballard, even, acquiring a high collector value when they earned their rarity by having the reek of disaster about them. Or collectors considering a dilapidated but original finish superior to the sort of work Ballard, Marlin and Nimschke would have been flattered to see done in the century after next.
My own Ballard also came as a barreled action, but is just the plainest type of Ball and Williams rimfire, not pitted but subject to every other sort of deterioration, and unsuitable for doing anything really exciting with. I wonder if factory information on a Marlin Ballard could be available, probably from the Buffalo Bill Center, as to the type of butt originally installed? Some would feel obliged to follow that, but I am not so sure the three gentlemen aforementioned would have worried. It isn't like it was an Austin Seven or something.
You have made that buttplate look very much in keeping. I think it did demand a bit of concavity in the line of the bottom of the butt. A pretty good line of Scheutzen buttplates is available from Track of the Wolf,
http://www.trackofthewolf.com/List/Item.aspx/696/1 . I once modeled a set in wax, buttplate and forend cap with sling loop, for a target Martini, and had them cast in stainless steel. I think a buttplate without at least the upper prong might be better for someone who plans on doing much shooting from a position other than standing.
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