jzeblaz
WKR
I haven't had any of these, but I have a 7mm-08 (great to carry and shoot) and a heavy 280 Rem. I can run the 168 LRX out of the 280 (1:9) at elevation, but they keyhole at sea level. Considering you have 280AI and 7RM, I'd be looking at the SAUM and making it light, especially if you can get it short/suppressed. That'd be the mtn rifle I'd build if I could get components. The PRC is interesting, and components likely to be more available as it is riding the wave of popularity at the moment. Sounds like a fun project, I hope you make a post to take us along with your build. Have fun!