I know of several .375 H&H's which have been cut down to 20", and most report a total velocity loss of only 50 fps. The .375 bore seems quite forgiving, and my 20" .375 Ultra is similar in this respect. You will not need any voodoo reloading procedures, or be overly concerned about powder burn rates. Just use good handloading procedures, and use the powder which is the most efficient for your bullet weight, typically H-4895, W-760 and R-15, etc.

Bruised -

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