Re: .338 Yellow Bastard FASTEST 338 Caliber on Planet Earth.
Sounds like the 338 Talbot (50BMG necked to 338). I do not remember how fast it pushed the 250's but it was way up there.
Long range shooting is a process that ends with a result. Once you start to focus on the result (how bad your last shot was, how big the group is going to be, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.