I'm not sure the 375 H&H would work thru that action. If I remember correctly, the 300 Win Mag was an H&H case, shortened to work thru a 30'06 length action. There were 3 model 70 Actions, Short - 308 length, Long - 30'06 length, and Magnum length, the last for the 300 and 375 H&H Magnums.
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There is the science of Ballistics and the Art of Bullistics
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