The best I have ever ran across in any of my 3 250s is the old (no longer in production) 52gr BTHP Winchester Supream in the black & red box, stock # S22250.
I hate it when a company has a great product and quits production of it just because everyone gets on a new bullet kick.
I have yet to find a factory 250 load that will touch the old supream ammo in my Winchester model 70 heavy varmint!
Everyone wants the B-Tips.
I have 2 Win model 70s, both 270 wsm and 3 Handis in 204 that love the B-Tip ammo but not my 250s.
That's why I always say, once you find an ammo that your gun likes, go out and buy all you can find of it because you never know when the factory will drop it!!!
LONGTOM