the best accuracy that we had was with a COAL of 3.560 which is longer than magazine length. This rifle was purchased used and I suspect the throat is a little shot out. But the 168's did shoot the best with very little jump to the lands...probably .002-.005". You'll have to see what works for you. With this load we consitently get groups in the .6-.9 moa range.
The max load sent to me by berger for that bullet was I think 72.5 grains, I have not shot this load yet so I dont have a velocity, but is supposed to be aroung 2950fps. Also, these retumbo loads in a 7mmRemmag are compressed loads, so the farther out you seat your bullet the less compression you will see.
I shoot 74.6 gr Retumbo, Federal GM210M primers, in my Tikka T3 with 24 3/8" barrel. This is hotter than most report using. But I get good case primer pocket life. My bullet is jammed into the lands 0.010"
Savage 112 BVSS, COL 3.442" (0.005" jammed, still fits in the magazine, bullet doesn't pull on extraction), 69.5g Retumbo, 2989 fps, Win Brass, WLRM primer. No pressure signs at all.
The sweet spot is quite wide in this rifle, 69.0g @ 2970 fps to 70.0g. @ 3035 fps. A ladder test showed that one shot each in 1/2 grain increments from 68.5g to 70.5g shot into a group .534" wide x .506" tall, max spread of .625". 3 of the shots went into one ragged hole. 69.5g was the middle of the one ragged hole charge range.