Howdy all, Quick, thanks for the reference.
I no longer have the BC but am seriously considering another. They are just plain fun to shoot.
On the tang issue, I don't think it's the BEST setup, BUT it was accurate. I talked to Lee Shaver (he did mine) in depth, over the phone about this before doing it. He was very helpful and is a very knowledgable singshot riflesmith. Lee and I agree the best setup is a sight on the barrel, but the next best is a welded tang, on the back of the receiver. Then cut the inlet out of the stock. You still have SOME variance, depending on how tight the breech closes, but it's a bit more stable then the wrist tang.
My current thinking is going more towards something like this
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mounted on top of the barrel. Still very period looking and should be very reliable and accurate.
Something like this from Brownells can be mounted right on the barrel too.
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Here is the link.
http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=12783Not as nice as a peep, but workable.