The powder Federal uses is non-cannister grade. Early Federal .470 varied considerably, lot to lot. I hear they're adjusting the charge now to allow for density variations between lots. 7.5% isn't surprising. I've run into that much with off the rack RL 15.

LGF:

What barrel length? I have no idea what data Federal is using, but the Kynoch standard ballistics for .470 were for 75 grains cordite and a 500 grain bullet for 2125 fps from a 31" pressure barrel. If your barrels are 24", 2060 fps would be fairly warm.
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