I see this old thread got some new life
I really do want a 257 Weatherby barrel. But... I think I have enough guns to hunt the world now so I've decided the first time I'm in a hunting situation where a good, handloaded round from 30R Blaser does not shoot flat enough I will get the Weatherby.
I agree totally that the rimmed case is not necessary in a modern break action single shot and offers very limited advantage. But then again why not. After using the rifle for two years I'm very happy with the chamberings. One issue was the reloading dies. They were expensive and had to be special ordered (they are top-notch Forster and Triebel dies though). In Europe brass is available and while not the cheapest not quite the rip off it is in oz. $5 is more than I paid for RWS factory rounds in 5.5x50R. Shot in one rifle and handled with common sense I get 10 loads out of a case. For me, in a hunting rifle, the cost of brass is more than acceptable. Hell, I shoot two or three dozen animals a month at most so even overpriced factory ammo would be ok. A dedicated range rifle pushing hot loads, or any form of dynamic comp shooting would perhaps be a different story but for hunting it just works.