So I have collected a few R700 barrels over the years. I have a heavy varmint contour barrel that I started observing a loss in consistiency. The round count was over 5K . "If I decide to attempt a rechambering what would be a good choice for target out to say 1K yds ? I am deeply vested into handloading so I have no real preference. I have a R700 Long action that i'm currently not using. I was leaning towards something of the 7mm family ?