Since the Reloader series of powders are now unavailable to the public, what if the benefit of the 300 PRC over the 300 Win Mag? Velocities are the same with available powders and at lower charge weights. Modern cartridge design, blah blah blah.
You can run 220s with the 300 Win Mags 1-10" twist.
I'm making an observation not an argument. I guess what I mean is if you have a good 300 Win Mag today, there is no appreciable difference worth "Upgrading" to. If you gave me a new Proof Research 300 PRC I would gladly take it!