The 300 Remington Ultra Magnum is like having five .30 Caliber Rifles in one.
( 308,. 30.06, 300 H&H,. 300 Win. and the 300 Wby )
And of course the 300 RUM which exceeds all of them.
That's six.
Don't get hung up in the little details. He's revolutionizing modern ballistics understanding with his mathematical work:
Velocity + Ballistics = Distance/Accuracy