I have one I built in 1964 on an FN Browning action, using a Douglas premium grade barrel, 26" , 1/10" twist. It is by far the most accurate rifle I have ever owned. It will (still!!) produce 100-yard 5-shot groups as small as .3" . The load that does this is 53.5 grains of H4831 with the 100-grain Sierra bullet. As mentioned, this rifle has a 26" barrel, in which this load produces 3300 FPS. My deer load is the 95-grain Nosler Partiton bullet with the same powder charge, nearly the same MV.

This gun is throated for the 105-grain Speer spitzer seated to the base of the neck, so with lighter bullets, this probably amounts to a form of " freebore" , like Weatherby uses. Nonetheless, accuracy with lighter bullets has not been adversely affected, but I never got acceptable accuracy with the 105 gr. Speer.

Working up a load for the 85 grain Nosler solid Base Boattail bullet, I got to 59 grains of Norma MRP, Lot no. 015303, for a muzzle velocity of 3623 FPS. BUT for a shooting load with this bullet, I dropped back to 57 grains of this same lot of MRP, which produces only an average velocity of 3496 FPS. I also got excellent accuracy with the 85-grain Sierra HPBT using 53 grains of IMR4350, but never chronographed that load.