JohnE, insightful commentary and questions; thanks.
The gun by itself is a static object with weight (measured), balance (measured), and moment of inertia at center of gravity (measured). Weight tells us the required effort to lift and carry. Balance (CG) tells us how the weight can be divided between the hands. MOI at CG tells us the effort necessary to change the direction the gun is pointing Before the gun is mounted (held in the hands), the MOI at CG is the best indicator of effort to change the direction of point. Depending on hand placement, it may not be exact for individual shooters, but it does tell us about the gun. When mounted to the shoulder, the axis of rotation shifts to, more or less, the shooters spine. Since we have no way to account for shooter physiology, we have to stay with properties of the gun itself. The best number is the MOI at butt which is calculated from MOI at CG via the parallel axis theorem. All numbers are gun properties (how the gun itself is) and do not account for shooter differences.
To use this information, a shooter must learn learn how it relates to him/her; just as is needed with stock fit. Once learned, it is repeatable. Again, as with stocking, you may want differing numbers for differing purposes.
Questions?
DDA
