Tennessee Gentleman wrote:
An old Army buddy and I are arguing about the phenomenon called "knock down power" [edited to add quotes]
Before we go any further, how do you and your buddy define the term "knock down power" and how do you propose to quantify and measure it? From what follows your original post in the thread, it seems as if you are equating it to momentum (mass times velocity) and that's a poor proxy as it fails to take into account the many masses that are involved, what velocities are being imparted to them, the time over which this is occurring and the higher order derivatives of velocity such as acceleration and jerk that apply.
Can a bullet knock somebody down.
-- Certainly.
----- I've seen it happen.
--------It has actually happened to me.
Can the recoil of a gun knock someone down.
-- Again, certainly.
----- I've seen it happen.
Does it always do that? Of course not. People aren't blown around the firing range like so many autumn leaves by the recoil of their guns. The discovery of the mechanisms at work to explain why some people get knocked down and others don't and how you would quantify and measure what's going on would be the start of any discussion of "knock down power".
Until you and your buddy define the term, further discussion or analysis of an undefined term using an inapplicable metric is pointless.
Within the last year on TheHighRoad.org, one of the members posted the entire publication history of the International Wound Ballistics Association's
Wound Ballistics Review. It's still available and makes for fascinating reading and a thorough study of it would be particularly useful for this conversation as it would provide a practical basis for formulating the concept of "knock down power".