Yes, get the brass first. I secured 200 Norma 300 saum cases before I went ahead with the conversion of my Savage LRP from 284 win to 7 saum. And of course I got the right bolt head. The velocity is between 2900 and 2950 fps with berger 180 vlds. It has X ring accuracy. Low pressure. I have pre ordered a couple of boxes of 195gr bergers and I have an 8.5 twist barrel in there and an 8 twist in storage. If we can get 2800 to 2850 fps with the new projectile I think it will be ok in the saum. There is no point using a bigger magnum if you cannot tune it to a winning level. My gunsmith has tried the 280 AI & the 7mm rem mag and has also switched to the saum. Having said that , it may be that the 7mm-300 wsm, or 7mm wsm is a better choice for the 195gr with powder a step slower. At the moment we are both getting good results and clean burning with ADI 2213SC (like H4831).