Originally Posted by 436
Not real sure'..., but.... you might look at 6.5 Rem Mag load data to help you work up; it's seem pretty close in volume... and performance to yours. I had one of the very early 6.5 Rem Mags in a Model 700... wish I still had it, a great cartridge.
The WSM case holds 7-8 grs. more powder than the 6.5 Rem so you should be able to load 3-4 grs. more than the Rem calls for. I have a similar capacity case in the 6.5 Sherman so you might use this for comparison:
Max loads for 140 Berger:
60 grs 7828
Hope this helps get you started......Rich