Accession Number : AD0853845

Title :   Yawing Motion of a Bullet After Penetrating a Thin Plate.

Descriptive Note : Memorandum rept.,

Corporate Author : ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD

Personal Author(s) : Braun, Walter F.

Report Date : APR 1969

Pagination or Media Count : 54

Abstract : When a bullet penetrates a thin plate and emerges relatively undamaged, the period of the subsequent yawing motion can be predicted from a knowledge of the physical constants of the bullet, the spin, the density of the medium after penetration and the static moment coefficient. The equations used to predict this motion are given. Several examples of the predicted motion are compared with empirical data. The effects on the period and the magnitude of yaw of small changes in the bullet characteristics due to impact on the plate are discussed, emphasizing the importance of obtaining sufficient data to describe the complete yaw period and sufficient information on the physical integrity of the bullet after impact. The importance of imparting the correct bullet spin when simulating real down-range test conditions is discussed. A comparison of test data taken under different spin conditions is given. (Author)

Descriptors :   (*SPIN STABILIZED AMMUNITION, SMALL ARMS AMMUNITION), (*ARMOR PLATE, PENETRATION), YAW, FIRING TESTS(ORDNANCE), EXTERIOR BALLISTICS, IMPACT, DEFLECTION, ANGLE OF ATTACK, MOMENT OF INERTIA.

Subject Categories : Ammunition and Explosives

Distribution Statement : APPROVED FOR PUBLIC RELEASE