Take your nock off , put some epoxie on a splitshot sinker and drop it in the arrow , that will do it , but changing your foc will change otter things allso , like spine , and point of impact ,and trajectory
A heavyer head , and lighter tail [read feathers] will do the same
Such as arrows with extremely high FOC (20% +) are showing significantly better penetration than arrows with more normal FOC's.
Very intresting ,I know he advocates 2 blade fixed heads allso . The bows and arrows required for buffalo , and african game , are putting out some serious energy , that Im sure is relative to the equasion