Ricochet Dynamics for the Nine-Millimetre Parabellum Bullet

The presence of extraneous markings on a fired bullet that has ricocheted off water depends on the angle of incidence of the bullet to the water and the depth of the water. An Uzi submachine gun, held in a machine rest, was fired into a large container of water at various controlled angles. The angle of incidence and the angle of departure of the bullet from the water were measured. The critical angle of ricochet, the depth of penetration, and the path of the bullet in the water were measured. The measured critical angle of ricochet of a 9-mm parabellum bullet fired from the above weapon was 6.5°. The maximum depth of penetration into the water during ricochet was found to be 22 mm. The maximum track length in the water was 62 cm.