I built a 7mm RSAUM for 1,000 yard competition this year. I thought about the .30 calibers and different cases and compared ballistics of different bullets at different velocities vs. recoil (since I shoot prone) and settled on the 7mm. I am pleased to say that I made the right choice for me. I see no difference in wind drift between my 7mm with the 180gr Bergers and the bigger 300 Win. mags. with the 190 and 210 grain bullets. In fact I'm outscoring most of them. As for the .30 RSAUM, I think the case may be a little small capacity wise to get the most out of the bigger bullets. If you want to stay with .30 you might want to look at the WSM or .300 Win. mag. case. But if you're willing to step down the 7mm has performed well for me.