If Heym can do it right, I believe the .400 Jeffery could outsell everything else.

However, It would be a mistake to build it on a smaller frame. The action Heym uses for the .470 is too small for caliber and the barrels don't have enough contour, so that there isn't enough weight between the hands, and the .470s are too light. Build the .400 on the .470 action and give the barrels the amount of contour a .400 should have. I bet it would come in at 9.5 lbs, with perfect weight distribution.

Also, ditch the short barrels. Heym can get 26" blanks if they want to.
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