Originally Posted by Buffalochip
I took the liberty of loading one of your earlier pics into Photoshop and messing with the contrast and brightness a bit. If that receiver and loading lever aren't casehardened, than I don't know what is. The hammer even seems to have some coloring. As you pointed out, the remainder of the gun metal is uniform in color and doesn't exhibit mottling due to age. I think some pics, taken outside without a flash and out of direct sunlight is all that is needed to conclude if it is casehardened or not. Now if that casehardening is original...
Well, figured I'd start with this - Here is the verbatim details from the official CODY letter for this rifle: Which matches it perfectly, but does not give any other info such as stock/checkering etc. ....
Barrel Type; Octagon
Received in warehouse on November 5, 1898. Shipped from warehouse on November 5, 1898. Order number 8549
No other information is available for this serial number."