Re: 300 RUM 210 Berger or 240 SMK
I personally shoot the 210 Bergers. They perform excellent past 1000yds. You gain on velocity and with a high b.c. you're not too far from the 240's
In my opinion that delivers better results than the slower 240's which will drop 150-200 fps.
My final authority in all matters of faith and practice is the King James Bible. It's still the monarch of books!!