ebd10, I built a 6.5x55 on a savage 110 action, I put a 28", 3 groove, 1 in 8" twist, heavy palma contour pacnor barrel on, I had them throat it for a 123 gr lapua scenar with the base of the bullet at the bottom of the neck.
I haven't done any long range work yet but it shoots sub 1/2" @100 yds and even more impressive is the velocities. I'm getting 3100 fps with the 123 scenars over 50.5 grs of MRP and 2997 fps with 142 matchkings over 49.5 grs of N165.