Here's something for you to look at.
Get out some manuals and compare the 257 Weatherby to the 25-06 with like barrel lengths.
You might be suprized to see how close they are.
If you doubt it, get a 25-06 with a 26" barrel and do some chronograph yourself (I have done that on 3 occasions with 3 Weatherby's and 3 25-06s that I made for customers in the last 20 years)
Again, seeing is believing.