Re: Making 300 RUM cases out of Norma 404 Jeffery cases?
Mainly time and effort, plus case life.
I have to cull out about 20% of the Remington brass that is way out when sorting. It shoots poorly before fire forming, (I can get sub 1/3 inch groups with lapua brass right out of the box with ZERO case prep!), it doesn't last nearly as long as Winchester / Norma / Lapua brass, about half the case life, and the necks are simply horrible (concentricity and wall thickness).
This isn't just with the 300 RUM, but virtually every bag of Remington brass I have purchased in the last 10 months or so. I had several cases with massively deformed necks / shoulders, some that I couldn't even use due to deformity or neck wall thickness that was 'unturnable'. It is like they don't even inspect them.