I will be backing my son up for a once in a life time brown bear tag for Red Lake on Kodiak. I plan to shoot 270 gr Hammer Hunters but have available a limited supply of med to med/slow powders. My first choice would be H4350 followed by W760 neither of which I have. I have an abundance of H4831 which Ken Waters suggests could be appropriate. I will be shooting a 375 Weatherby in a pre-64 Win M70 with 22” barrel. Does anyone have any experience/recommendations for this particular combination of caliber/bullet/powder? Just in case, I have filed off the front sight.