Regarding actions only, please compare quality of fit and finish, and metallurgy, of Browning-Miroku 1885 and C. Sharps High Walls.
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I have an opportunity to acquire a Browning 1885 in 7 mm Remington Magnum and/or C. Sharps in 38-55. How difficult, how expensive would it be to convert either action to 45-70 or 50-90? How reliable would such a conversion be?
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I understand some Browning 1885s have [top] tangs and some do not. What can be done to a non-tang action that it will accept tang sights?

I would get the C.Sharps and send it to them for the conversion, then you get their accuracy and a Badger barrel. I dont think you can get it in larger than 45 caliber.

I have never held a Browning-Miroku 1885 and I believe they are good guns. But comparing C.Sharps rifles with any gunstore rifle around they seem like a bargain to me. All that craftmanship and still competitive pricing.

Mine is in the "Accurate Highwall" thread on this forum.