Gonna be a .257 Roberts. Original doner gun was a .22 Hornet. For some ungodly reason the original number 3 stock was cracked once on the forearm and on both sides of the buttstock so it most likely be used as a pattern stock. Current thought is 23" barrel instead of the 22". Machined quarter-rib that extends back over over the receiver machined for Talley sights, also to include two folding (Safari-type) sights.
Straight stock with pancake and Biesen steel buttplate.
Gonna mount a little Leupold VX-III 2.5 x 8. Wanna keep this pretty lean and mean.
PS. Well, above is at least the current plan.
That sounds like a hell of a good plan to me! The .257 Roberts is a great choice of caliber. I agree with Mr. Hughes about the "wedding band". In fact the standard transition from octagon to round looks the best to me, but that just me.
One thought about the scope. As for making the rifle a little leaner, the Leupold VX-III 2.5 x 8 is a great scope, but you might consider a Leupold VX-II 2-7 x 28mm Ultralight. It's an inch and a half shorter, 3.2 Oz. lighter and not as big around.
IMO, smaller is better when it comes to scopes if one wants the handling qualities of a fine rifle, like you are building, to be really good.
I really look forward to seeing your finished rifle.
I have a Ruger No. 3 in .30-40 Krag, that I am fond of.