I'm still up in the air right now about which one to go with.
I will most likely want to shoot 200+gr bullets out of the gun with a 26" or so barrel and would obviously like the best ballistics that are feasible without being a barrel burner. But it is a hunting gun so I'm not overly concerned. I would like to get 1500 rounds of good life out of it.
The one thing I don't want to build is a gun that I have to eventually fireform the brass for or turn into a guy that hunts brass more than I hunt with the gun. The 30 Hart (300 weatherby based) that was mentioned earlier seems to have good brass availability now but back in 2014 I couldn't find brass for it anywhere. Maybe and hopefully those days are well behind us. The 300 RUM has been discussed on brass and I agree. I really liked the 300 Norma that was mentioned. No belt, factory brass, good performance...seems like a nice compromise of the factors that I'm looking into. The 30 Nosler fits into that category as well except the brass is only carried by Nosler at the moment. That worries me a little in times of crisis but a viable option.
I was hoping an owner of a 30-338 lapua would chime in at some point to share an opinion. Maybe the lack of response is an opinion in and of itself. My thoughts on the pro's of that caliber were good brass, brass options and availability, and the idea that I could run it mild on the reloads and get at or near 300 RUM performance and have the brass last forever and decent barrel life. Maybe it's not worth it.
I never thought about the action restriction/requirements of the options I've mentioned. More specifically, would the 300 Norma and 30-338 options work on a magnum based r700? I probably will go the custom route when the time comes but I was just curious.
Thanks for all the replies so far guys.