257 weatherby fast twist is bad ***, but honestly I think on the upper edge of what is useful. I have 1.
I know people are shooting 25PRC type rifle nearly as fast as I am pushing mine, and I know mine is loaded on the upper edge of pressure.
I love mine, but if I didn't already have the action, brass, dies, and I wanted a fast 25 cal. 25 PRC would probably be it, built on a long action.
I almost had mine turned into a 264 Weatherby for fun since they never actually made 1, but the 257 is a beast too so I stayed with it.