Ricochet of 9 mm pistol bullets on glazed ceramic tiles: An empirical study in support of shooting incident reconstruction.

Experimental ricochet data on the most commonly found bullet-target combinations in shooting incidents are contemporary necessity in conducting ricochet analysis during shooting reconstructions. As bullet ricochet behavior and associated evidence production are affected by various factors, understanding specific phenomena related to each bullet-target combination is essential for shooting investigators to reconstruct bullet ricochet incidents accurately. However, there is a significant lack of empirical data in this area despite the significant demand. Building on a previous study conducted with rifle bullets, this empirical study explores the ricochet behavior and surface evidence when 9 mm Luger pistol bullets ricochet off glazed ceramic wall and floor tiles. The study highlights the critical angles of bullets for floor and wall tiles (14.8 degrees and 16.6 degrees, respectively), and different bullet ricochet trends when 9 mm bullets ricochet off standard wall and floor tiles. This paper introduces for the first time in a ricochet event, the "caterpillar effect" or "caterpillar impact mark" and the first observation of the "nucleus" ricochet mark for pistol caliber bullet ricochets, both of which are important novel findings. This study further demonstrates the significance of undergoing practical and relevant ricochet experimentation for the accurate reconstruction of shooting incidents.