I'm often asked why I have so many rifles in the same chambering. The answer is simple, I don't like to mix loads through the same rifle, there are pristine cast boolit shooters, and then there are the "other" types. Most of my CB shooters started off with new barrels and have never seen copper material, and never will.
The benifets are plenty, a good barrel that will never wear out, mirror finished by use.
My Springfield 30.06
Best 10 shot group with the 30.06
50/70 cal 1874 Sharps
223 Remington soon to be CB only after dabbing in PC