I think this thread is a good idea. Here's my take on the 7mm WSSM:
For use with Short Action, Magnum Bolt Face
Pros:
7mm has *lots* of good bullet choices from hunting to long range to varmints
The short case works well with short actions, with long high BC bullets still seated above the shoulder
Even with a long throat, loaded rounds are easily less than 2.8" COL so magazines are no problem
Cartridge has a case capacity between the 7mm-08 and the 284, both of which run into mag length and capacity issues with heavy bullets
Medium case capacity means lots of powder options with a medium or medium-slow burn rate
Works well with a 7mm WSM switch barrel, uses same bolt, magazines, bullets, etc.
Much better ballistics than a 308, and much better barrel life than a 7mm WSM (good compromise for high volume match shooting)
Relatively cost effective for its level of performance
Cons:
It's a wildcat, so no factory ammo, need custom dies, custom barrels, annealing WSSM brass to neck up, etc.
Recoil is not bad, but it's more recoil than most 6mm or 6.5mm when shooting 180's and could be a factor when you need to call your own shots in a match
WSSM is not one of the Uber-popular rounds so brass may be hard to find (although the brass I'm using was about the only thing sportsmans warehouse still had in stock...)
As far as ballistics, in a short action it's hard to beat a 7mm WSM, but I think the 7mm WSSM is a good compromise for shorter ranges and more rounds. I've been using a load with the berger 180 hybrids at 2800fps; run the numbers on those and compare with the 308, 260, etc. Some more info is here:
http://www.snipershide.com/shooting...199189-7mm-wssm-7wsm-switch-barrel-comps.html