OK, I need some opinions. I was originally going to have a .325 WSM built in a lightweight rifle. Then I decided the .325 didn't offer much for my needs, and decided on the .300 WSM with a carbon wrapped barrel. My thoughts now are this: Don't spend the money on the carbon wrap, but instead have two barrels chambered, a #1 contour in .300 WSM, and a #3 contour in a .325 WSM. The McMillan Hunters EDGE stock I have decided on is CNC inletted for a #3 contour and below. I will then have a rifle versatile enough for anything from pronghorn to brown bear. One question I have, are people truely not getting the performance out of the .338 WSM that the .325 WSM offers?

How light are you planning on making this rifle?
At one time I thought of doing the same thing as you but ended up using 2 rifles instead. One super light rifle for mountain hunting,
6lb 7-08AI, and one heavier rifle for bigger game, 8lb .338. This has worked wonderful so far. I'm even contemplating using the .338 for sheep hunting this year as 8lbs isn't too bad to pack around and the .338 has lots of reach. As far as the .338 WSM and .325 WSM, they won't have near the versatility of the standard .338 (IMO). Good luck with your project.