rem 700

I would get some 777 FFG and Pyrodex RS and try different powder charges with both of those bullets. I've used both of the bullets you mentioned in my T/C Omega with good results. The 300gr XTPs favored a smaller charge (110), but the 250gr shockwaves work great at 120-130grs RS. I would start small, about 90gr, and work up shooting 3 shot groups and increasing powder by10gr at a time.