Experimental simulation of reentry shots using a skin-gelatine composite model

Abstract

A bullet that has passed in and out of one body segment may continue its way into another part of the body causing a second entrance ("reentry") wound, which is often said to have an atypical and sometimes confusing appearance. To analyze this problem in a systematical approach, 9-mm Parabellum full metal-jacketed projectiles were fired at skin-gelatine composite models simulating the consecutive passage of a bullet through two parts of a body. When there was a distance between the two segments, the primary exit and the reentry skin wounds did not show any distinctive features differing from usual gunshot injuries. In the case of contact between exit and reentry site, the corresponding skin wounds resembled each other as both had central tissue defects surrounded by abrasion areas. The subsequent investigation of the simulant revealed that skin particles from both the exit and the adjacent reentry site had been displaced in the direction of the shot along the whole bullet track of the second segment. The morphological findings are presented and discussed with respect to the pertinent literature, and possible physical ballistic explanations are suggested.

GSR deposition along the bullet path in contact shots to composite models

“…Gelatin blocks measuring 25×12×12 cm (length of the bullet path 25 cm) were prepared in accordance with the recommendations for ballistic gelatin in a 10% concentration [7,8,10,13,28,34,35]. Skin pieces from the belly region of freshly slaughtered pigs were fixed to the front ends (12×12 cm in size) of the gelatin blocks with dental instant glue (Renfert, Hilzingen, Germany) in the areas of the later entrance and exit site.…”

Investigation of bullet penetration in ballistic gelatin via finite element simulation and experiment

“…The parameters are inserted into Eqs. (6) and (7) to obtain the rate-dependent shear modulus [25][26][27][28]. In these equations, the maximum indentation length of the probe is denoted asand the time when the stress relaxation starts is denoted as R t .…”

“…Some relevant research into wound ballistics has been conducted previously [1][2][3][4][5][6][7][8]. Bullet penetration phenomena are influenced by many factors such as the type of bullet, rotation and traveling speeds of the bullet, and the impact angle.…”

“…Furthermore, when a bullet hits bone or organs, the resistance forces exhibit sudden changes in magnitude and direction; these forces cause further decelerations and rotations of the bullet. In order to understand these chaotic phenomena, there have been some relevant studies looking into the experimental analysis of ballistic penetration for many materials (e.g., gelatin blocks and soap) [1][2][3][4][5][6][7][8]. In Ref.…”

“…A firm understanding of the impact of bullets on a human body is important for both improving the survival rate and also for developing efficient ammunition and bullets. To understand wound ballistics, many theoretical and experimental studies have been carried out [1][2][3][4][5][6][7][8]. However, it is still a difficult subject due to the chaotic behavior of highspeed impacts and the various rate-dependent material behaviors [9][10][11][12].…”