I hear you. They say that Norma brass is to soft too, and I have a batch of 280 Rem brass that I fire formed for my Ackley and it seems to be holding up fine with max loads. That brass is very consistent for weight too. I've heard folks talk positively about RWS 300 WM brass but I can't find any to check out. The shortest life brass I had for my 300 WM was Remington. Loose primer pockets after 3-4 loadings.
Huningtons usually has RWS 300 win.I bought some from them last year and my sample was as good as people say it is.
