  terminal ballistics, a sub-field of ballistics, is the study of the behavior and effects of a projectile when it hits its target.terminal ballistics test and analysis guidelines for the penetration mechanics branch - brl terminal ballistics is relevant both for small caliber projectiles as well as for large caliber projectiles (fired from artillery). the study of extremely high velocity impacts is still very new and is as yet mostly applied to spacecraft design. ==general== an early result is due to newton; the impact depth of any projectile is the depth that a projectile will reach before stopping in a medium; in newtonian mechanics, a projectile stops when it has transferred its momentum to an equal mass of the medium. if the impactor and medium have similar density this happens at an impact depth equal to the length of the impactor. for this simple result to be valid, the arresting medium is considered to have no integral shear strength. note that even though the projectile has stopped, the momentum is still transferred, and in the real world spalling and similar effects can occur. ==firearm projectiles== ===classes of bullet=== there are three basic classes of bullet: * those designed for maximum accuracy at varying ranges * those designed to maximize damage to a target by penetrating as deeply as possible * those designed to avoid over-penetration of a target, by deforming to control the depth to which the bullet penetrates, which as a by-product, deals more damage inside the wound. the third class may limit penetration by expanding or fragmenting. ====target shooting====  for short range target shooting on ranges up to 50 meters (55 yd), aerodynamics is relatively unimportant and velocities are low. as long as the bullet is balanced so it does not tumble, the aerodynamics are unimportant. for shooting at paper targets, the best bullet is one that will punch a perfect hole through the target. these bullets are called wadcutters. they have a very flat front, often with a relatively sharp edge along the perimeter. the flat front punches out a large hole in the paper, close to, if not equal to, the full diameter of the bullet. this all
Ballistics