Shoot a .300win.mag or .300wby mag and see how that recoil feels...the .300RUM should be even greater than either of these but more int he same class as these, than a .30-06 or 7mm rem.mag.

From what I hear the .300RUM is a step up from the .300win.mag. and a .300win.mag is certainly a step up from a .30-06...

in a heavy rifle, you can probably tolerate the .300RUM, but do you really want to?