knock down formula

[rr1220]

in my search for an answer as to a 120gr bullet is enough
for rams at 200 meters i found a calculation that can be done to answer that question Mb=(WxV)/225200
Mb=striking momentum...W= bullet weight...V= velocity in fps,using ballistic table to determine at a particular distance,my mv for my load is 2000fps=1630 at 200 meters
W=120-V=1630....195600/225200=.868.........it is suggested that a minimum of .7 of stiking momentum is needed for big bore targets
hope you find this useful for yourself if not just interesting