BoatTail
Well-Known Member
Is it possible to form WSM Brass, out of the full size Ultra Mag Brass? I know the case head and web is slightly smaller on the Ultra Mag. I also know I will likely need a set of forming dies. I'm finding it harder and harder to find WSM brass and looking for options. I have lots of 300 Ultra mag brass and no longer have the rifle. Just wondering if I can form it 90 % of the way, if fire forming would push out the web, remaining case and shoulder to WSM sizes. The need is 270 WSM mostly.