A NEW CASUALITY CRITERION
ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD
Pagination or Media Count:
The passage of a small missile through a soft medium is compared with its passage through steel and a point of view is adopted sufficiently wide to embrace the behavior of both media. Though surprise has often been expressed at the large cavitation produced in soft media, it is shown that this cavitation is to be expected, and of the observed magnitude. The results are applied to the experiments made to throw light on the wounding power of small fragments. The 58 foot-pound criterion was originally put forward for application to bullets weighing an ounce or more. For very small fragments it is proposed that a new criterion could be founded on the size of the momentary cavity which they produce - the requirement being the formation of a cavity of diameter greater than a certain minimum. If m is the mass of the fragment and v its incident velocity, this leads to the relation mv3 constant. When the value of the constant is chosen to agree with the 50 milligram missiles used by Black, Burns, and Zuckerman, it is found that on extrapolating to greater masses, it leads to the requirement of 57 foot-pounds for a one ounce missile. Thus the criterion based on very small fragments is in sufficient agreement with the older criterion for larger masses. Methods of applying this criterion to the estimation of casualties are discussed.
- Theoretical Mathematics