I bought a 257 Roberts back in the 1980's, when Remington issued their 700 "Classic" in that chambering.
Original barrel shot lights out with boattail bullets, but did not care for FB ones.
Since I bought it to hunt, and use Partitions a lot, I had a similar contour Shilen screwed on.
The thing was unreal!! It grouped almost every bullet I tried well, and the 115/120 partitions would regularly turn in groups around 5/8"
I took a fair bit of game with it, including a couple of moose, using the 120 Partition at 3060 fps. [yes, you read correctly, lol]
No flies on the 257 Bob. Mild recoil, accurate and effective.
Regards, Eagleye.