Bushmaster1313: Pay attention to "gregintenn" - as he is right on!
If you had ever shot a Winchester Model 70 in 257 Roberts you would have appreciated it, GREATLY!
The perfect Rifle in the perfect caliber!
AMEN!
I have three of them in my collection two standard weight Rifles and a Supergrade Rifle - I don't believe the factory offered a Featherweight in 257 Roberts - special orders not withstanding.
And YOU halfway answered your own question actually - the "supply is limited" THAT is indeed what is driving demand.
Having said that there are many other chamberings and models of the Riflemans Rifle that command higher prices than the 257 Roberts.
Comparable condition Rifles in 30/06 and in 257 Roberts - yes indeed the 257 Roberts offering would be NOTICEABLY higher in value than the most common calibered Model 70 (the 30/06).
As strongly priced as they are (257 Model 70's) if I saw one for sale today I would investigate and contemplate buying it as an investment.
So there ARE some folks who would buy Model 70's in 257 Roberts - I don't know if those "some folks" are driving a demand or not but based on 40+ years of observations 257 Model 70's usually sell very quickly when offered up.
Hold into the wind
VarmintGuy