Since the development of the 25-06 a lot of new cartridges have come out. Any worth necking down to .25 or is the .257 Weatherby as good as it gets?

I've had 257 Roberts, 25-06, and the 257 Weatherby and at least two of each and from my personal experience the 25-06 is as good as it gets and the 257 Roberts isn't much in arrears.

If you really want something better I'd heartily recommend the 6.5-06....it's a slightly upgraded 25-06 with some amazing performance.

Magnums aren't really helpful until the bullet gets to .358 diameter

Neck a .300 SAUM to .257 and you'll get a screamer. The .257 STW is way over bore, and the WSM would be a little to overbore to still be a benefit. Although the brass may be available longer.

Bottom line though, IMHO your not gaining a lot. Nate

It's not the next 25-06 but if you have or want to use a shorter stiffer action, the 25 Souper (25-308) is a nice package, more than the Roberts but only a little less than the '06