I found the old book. I have two sets of readings for it. One load is the Nosler solid base. Five shots. Hi shot was 2805, Lo shot was 2754. Extreme spread 51 FPS This was a 150 grain bullet.

The second load was the Nosler Ballistic tip. Five shots Hi shot 2900 fps, Lo shot 2855. Extreme spread 45 fps. 150 grain bullet.

Both loads were with IMR 4064. 47.0 grains WW LR Standard Primer. WW Brass. These loads were safe in that rifle but should be approached with caution in another rifle. I can't recall the barrel length of the 600 Rem but it was short. Either 18 1/2 or 20 inch. Maybe someone with a better memory than me can tell you for sure. These loads are from an old Hornady Manual. I would quess that the new manuals are a bit more conservative.