Their rifle catologue is OK.

However, from the ammo catologue and on the 300 RUM

"Simply the biggest, baddest, flattest-shooting 30 caliber
in production today. At 200 yards, it delivers 485 ft.-lbs.
more energy than the 300 Wby Mag and 28% more
energy than the 300 Win Mag or 300 WSM."

Last time I looked 30/378 ammo was still being produced

Mike