Glad you are looking at the 200 grain bullets for the Wby Mag. That's where these 30 cal magnums should be run, in my opinion.

One bullet you might want to check out is the North Fork 200 grain. Used those in my 300 H&H around 3,000 fps on game the size of elk in Africa (kudu, sable, nyala and waterbuck) and they worked incredibly well. Mike Brady is fantastic to work with also.
http://www.northforkbullets.com/