I don't have the Lyman manual here but I'm pretty sure it suggested the use of a standard primer for all of the 300WM loadings. I know for all the powders that I have it suggests a regular primer. Next batch I load up will be with the magnum primer for sure.

I ordered the Nosler Volume 5 Reloading Manual today.

BC - As son as I get the Nosler book that is exactly what I'm going to do. I'm going to compare the starting and max charges to see how much they differ.

Thanks for all the responses.

Tom