I have been shooting a Weatherby Deluxe in 257 Weath. Mag for the past couple of years.. Mainly shoot 115 ballistic tips, averaging around 3390-3420 fps depending on the box of ammo.. Had the rifle accurized by Hill Country Rifles in Texas, worth every penny. Went from 1 inch groups to sub-moa with all factory Weath. ammo. Shot an Elk in Craig Colorado last year at 280 yds with a Barnes 115 gr. high shoulder shot/spine dropped the elk in its tracks. I was a little cocerned about light bullet performance but it worked great. The 100 gr. SP's absolutely destroy deer at under 150 yds. its like a small explosion went off. Ballistic tips may have similiar performance. Good luck with your 257 W