I found the 270WSM to have noticable recoil with 150gr comparied to 270. This was mainly with slower powder. But definate notable improvment with velocity. You can get an extra 150fps with the WSM especially with factory loads. Alot of people can brush that off like its nothing, but folks thats almost the difference of a 300win mag and 30-06. Keep that in mind.

Basically, way I looked at it, you can getbullistics of a 130gr bullet with a 150gr bullet in a WSM. I knowsomepeople who get 3100fps with 130gr bullets in thier270win, but I nevercould reach that myself with accuracy.