Which calibers of brass can be simply necked down to 7mm WSM?

[The Gobble-stopper]

Have a friend that owns a 7mm WSM he is reloading but only uses the brass from his factory loads. And doesn't have a good supply. Or the extra money to buy empty brass. Thus he hits the popular ranges in the area to look for brass. With no luck. I know I use 30.06 brass for my .270, is there a more popular brass that he can use and neck down without any trouble to be used in the 7mm WSM. I tried to do research on the net, but couldn't figure out how to ask the right question. I thought I saw that simply running the 308 brass through his die would work. Is this true. And are there any other calibers that can be necked down. Without extra steps?

[theleo]

He can use 270 or 300wsm brass, the shoulder is moved forward on the 7mm so it should be fire formed before he starts loading anything for top end accuracy. There's no cheap common brass it can be made from though.

[Skillet]

 

Here's a good read-

http://benchrest.com/showthread.php?85461-7-WSM-from-300-WSM

[The Gobble-stopper]

Thanks guys, I will pass on the knowledge...