In my opinion and from my experience with the two, if you can shoot a 300 WM well, you will LOVE a .338!
I find a 300 WM to have a pretty harsh, unpleasant recoil. Whereas the .338 is more like a big push.
Mind you, my 338 is a sporter while my 300 is in a Sendero, so.. they are different rifles. But then, the Sendero is MUCH heavier rifle and the recoil is still noticeably faster and harsher.
