Well, I checked out case capacity, 70.6 grains of water.

I looked here, http://kwk.us/cases.html, and found the 9.3x62 is 77 grains, 35 Whelen is 71 grains, and 35 WCF is 69 grains.

My Lyman book has a 250 grain load with 46.0 grains of IMR 3031 at 35,400 CUP, so 42.0 grains is probably a reasonable load for this rifle.