Citation

Tsach T, Landau E, Shor Y, Volkov N, Chaikovsky A. J. Forensic Sci. 2009; 54(1): 77-83.

Affiliation

Toolmarks and Materials Laboratory, DIFS, Israel Police Headquarters, Jerusalem 91906, Israel. simanim@police.gov.il

Copyright

(Copyright © 2009, American Society for Testing and Materials, Publisher John Wiley and Sons)

DOI

10.1111/j.1556-4029.2008.00930.x

PMID

19120826

Abstract

The correlation between bullet hole shapes in metal and projectile impact velocity was examined. A series of shots were fired from an M-16A1 assault rifle of 5.56 mm caliber toward a 1-mm thick metal target. All shots were fired at a perpendicular angle to the metal sheets, and the velocity was measured just before the projectile hit the target. Velocities ranged between 400 and 900 m/sec. From the replica of the shooting hole, a perpendicular plane was created, showing the symmetrical properties of the hole. The best mathematical equation describing the shape of the entrance hole was the exponential function in the form: Y x = A + Be kx. The empirical equation of the hole defined using the regression method is: Y x,V = 8.268/V 0.578018 e(0.584x/V0.005). This equation describes the general shape of shooting holes created by velocities ranging from 440 to 750 m/sec. From this equation, one can estimate the bullet velocity when it hits the target.

Language: en