I’m sure this has been discussed here already but here it goes . If you were building a 300 win mag to shoot 215 bergers how would you throat it ? Saami ? Custom throat freebore ?
You want a chamber of 3.600 inches (0.050" Free Bore) for the Berger 215's and 230's, and 3.700 inches (0.150 Free Bore) if you plan on shooting monolithic or 250 grain bullets. Also, I would do a 1:9 to 1:8 twist for the heavier bullets.