Your going to have to make the stuff from 300 WSM or 270 WSM ?
It can be neck down then you got to fireform it another step. What season is the season for 7mm wsm brass anyway?
This advice sounds unsafe to me. I would not do it.Just neck down some quality 300 WSM brass and you are good to go. No "false shoulder" is created by simply necking the .308 neck down to .284.
This advice sounds unsafe to me. I would not do it.
The case may not headspace properly on the small shoulder left by resizing the 300 WSM case in a 7 WSM die. An incorrect headspace of up to 0.10" could result, which could lead to case rupture. For example, I know for a fact that resized 300 WSM cases do not headspace correctly in my 7 WSM chamber.
I resize, fire form at low pressure, and then check headspace with a Wilson headspace gage. Only then do I load the case to full pressure.
I believe Varmint Hunter is talking about re-chambering to 7-300wsm as stated in a previous post which would give the chamber the same shoulder as a 300wsm correct? I'm not trying to stir anything up I have just been considering doing this and trying to learn more about it