Just a couple observations. The common bullet weight was 77 grains, but weight was mostly important as to how it affected length (for accuracy) and velocity (heavier=lower velocity). Solid copper bullets result in longer bullets for the same weight and unless the shanks are grooved will drive pressures up. If you want a little higher velocity. you might try 70grain composite bullets. Carcano's mention of Norma using an unstable Bofors Powder brings to mind the fact that they replaced their "slow" powder N 205 with MRP back when I was a young man and others were still a "gleam in your old man's eye". Trying the more stable slow powder Norma MRP might be an option or going back to old and tested loads using 4350 or 4831. Some older 70 grain bullets proved unusable, not because they weighed 70 grains, but because the jackets wouldn't hold up to the velocity. New/harder jacketed bullets weighing 70 grains should be OK unless its modern length makes it too long for the rifle's twist rate. Old ballistic data showed two different velocities for the same bullet in the 5.6X61 vom Hofe SV. Unfortunately, it wasn't always clearly shown that the higher velocity (3700+fps) was only for the rimless version, and the lower velocity (3400+fps) was for the rimed version. It will be hard enough to achieve 3400+ fps with the rimed version and most older users stopped at around 3250fps to prevent damage to a fine rifle.
Mike