Encore28:

I loged on to the Weatherby site last night, and I could not find any information on Weatherby Vanguard .257 Wby. Mag. if you get a chance call them at 1 (800)227-2023.

I own a Weatherby Mark V Sporter .340 Wby. Mag., and if I do my part, it will shoot .408" groups all day. Good luck.