Although not very common, forensic investigation related to projectile ricochet on water can be required when undesirable collateral damage occurs. Predicting the ricochet behavior of a projectile is challenging owing to numerous parameters involved: impact velocity, incident angle, projectile stability, angular velocity, etc. Ricochet characteristics of different projectiles (K50 BMG, 0.5-cal Ball M2, 0.5-cal AP-T C44, 7.62-mm Ball C21, and 5.56-mm Ball C77) were studied in a pool. The results are presented to assess projectile velocity after ricochet, ricochet angle, and projectile azimuth angle based on impact velocity or incident angle for each projectile type. The azimuth ranges show the highest variability at low postricochet velocity. The critical ricochet angles were ranging from 15 to 30°. The average ricochet angles for all projectiles were pretty close for all projectiles at 2.5 and 10° incident angles for the range of velocities studied.

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The process of shaped charge jet formation, fragmentation, and penetration in rolled-homogenous armor steel target plates was investigated using the explicit, nonlinear Lagrangian finite element method. The investigation was conducted in two dimensions utilizing an axisymmetric configuration for a shaped charge with a 40 mm cone diameter. The results obtained using numerical simulations were compared to the experimental results obtained from tests. In addition, the dynamic behavior of the jet was compared to the visual data obtained from X-rays to confirm jet formation and fragmentation predictions. The advanced features of the developed shaped charge model include adaptive remeshing to follow the high deformation pattern of the jet, appropriate constitutive material models and equations of state to account for high strain rate, and restart files to allow the simulation to be performed in stages.