I have had a number of 257 Weatherby's, Mark 5's, Vangaurds, one custom Mauser, and 700's. I shot the barrels out on coyotes, chucks, and jack rabbits....one heck of a splat with 90g Sierra bthp.
I had a reamer ground with zero freebore than another with .070 freebore where you could neck down 264 WM brass to 257 Weatherby in one pass through a full length sizer with it's slightly shorter neck with a perfect double radius shoulder.
ON short freebore 26" barrels, 100g bullets are doing 3850 shooting groups in the 3's and smaller, 80g TTSX is bug hole accurate at 4150 fps with R#19. 115's are doing 3600, with both the 100 and 115g shooting R#22 with Fed 215's, all of these are with zero to .070 FB chambers.
I have one left today, a 9T, 25", shooting 115g Bergers at 3590 fps and it is a Hammer of Thor., R#22 and 215's taking about 15 or so rounds for load development.
A lot of us older guys cut out teeth on super fast, low BC Rounds. In today's world, we have the advantage of higher bc rounds. My world was turned upside down(the light came on) when I started shooting 180g Hornady ElD-M_.796 BC) in a 280 Rem...jeez, where the heck have I been?
You may want to re think your bullet choices?
