Some T/C .45-70 barrels are great, some are poor. One way to tell is to look at the throat - if it is short to non-existent then I would not look for 1 moa - more like 3-5 moa unless you are lucky. If the throat is longer and tapered, then the accuracy potential will probably be much better.
My Contender carbine barrel has almost no throat and it took a lot of load development to get a consistant 2 moa load. Most loads that shot very well in my four other .45-70s only shot 4-6 moa out of the Contender.
I don't know why the different throats, but it does matter and there are plenty of .45-70 shooters who know it.
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