What is the basic cartridge?

[longwinters]

What is the basic cartridge that the 270wsm and 300wsm are built on? If I am not being clear, what is the cartridge that the brass is taken from?

Long

 

[bowhuntrrl]

The parent brass is .404 Jeffrey, I believe. I know for certain that's what my .300 RUM came from and I use the same shellholders for both calibers.

 

[JD338]

The parent case for the RUM, SAUM, WSM, and WSSM is the 404 Jeffrey.

Regards,

JD338