RE: 257 Roberts is VERY impressive!
Always wanted a .257, so I built one last year on a '96 Mauser action. Turned out pretty good, and I am considering building another on a '98 action, too. Took two whitetails with it this past season, and proformance was all you could ask for despite the rifle needing some fine tuning. Load was Hornady's 100 grain interlock spitzer over H-4831 SC. I am impressed with the .257, too!