Woundary ballistics of biological tissue’s plastic deformation on the model of ballistic plastiline using hollow point and shape-stable bullets

Abstract

Introduction. Modern military conflicts make many challenges for military surgeons associated with the use of new types of weapons – hollow point bullets. The solution to this problem, firstly, depends on studying the characteristics of the terminal ballistics of such ammunition and comparing the data obtained with the characteristics of traditional weapon.
 The aim of the work is to conduct experimental modeling of the wound canal and residual wound cavity, which is formed due to plastic deformation from hollow point and non-hollow point bullets.
 Materials and methods. The studies were carried out on 40 blocks of ballistic plasticine, in each of which one shot was fired from an AKS-74 assault rifle and a ZBROYAR Z-10 carbine. Depending on the type of ammunition, the blocks of ballistic plasticine were divided into 4 groups: Group 1 – 10 blocks into which shots were made with 5.45 mm non-hollow point military cartridges with "PS" bullets with a steel core "7N6"; Group 2 (10 blocks) – 5.45x39 mm cartridges with "V-Max" hollow point bullets; Group 3 (10 blocks) – with cartridges 7.62x39 mm; Group 4 (10 blocks) – cartridges 7.62x39 mm with hollow point bullets of the "SP" type.
 Results and discussion. Only for a 5.45 mm military cartridge with "PS" bullets, both inlet and outlet bullet holes were detected in all 10 observations. When using non-hollow point bullets, the outer area of ​​the bullet inlet correlates with the caliber of the projectile (1.6 times larger when using 7.62 mm bullets). For hollow point bullets, the caliber of the projectile does not significantly affect the area of ​​the inlet (P < 0.05). The expansive properties of the bullet significantly increase the area of ​​the bullet hole by 14.87-31.2 times compared to non-hollow point ammunition. Increasing the caliber of the non-hollow point bullet leads to a significant increase in the area of ​​the sagittal section of the residual wound cavity in 1.59-2.03 times; whereas the expansive properties of the bullet do not significantly affect either the perimeter or the area of ​​the sagittal section of the residual wound cavity. For non-hollow point bullets, the volume of the residual wound cavity is more correlated with the caliber of the bullet (increases by 3.36 times); whereas for an hollow point bullet, its caliber has a smaller effect on the volume of the residual cavity (increases by 1.37 times). The expansive properties of the bullet affect the volume of the residual wound cavity in two ways: for 5.45 mm bullets the residual wound cavity increases 1.49 times, for 7.62 mm bullets it decreases 1.65 times. The use of hollow point bullets of 7.62 mm leads to greater collateral damage (zone of secondary necrosis, molecular shock) due to the scattering of the kinetic energy of the bullet to the elastic deformation of near-woundary tissues compared to non-hollow point analogues. The use of 5.45 mm expansive bullets leads to the formation of a larger volume of irreversible damage due to plastic deformation compared to non-hollow point analogues.
 Conclusions. The resulting model of plastic deformation of soft tissues, depending on the type of modern small arms, showed the dependence of the spatial configuration of the inlet bullet hole, residual wound cavity and deformation and fragmentation of the bullet on the caliber of the cartridge and its expansive properties.

Gunshot injury to the colon by expanding bullets in combat patients wounded in hybrid period of the Russian-Ukrainian war during 2014–2020

“…Such ballistic properties might be associated with severe abdominal trauma: multiorgan injury, multiple perforations of the bowel with massive fecal diversion, as well as a high risk of bleeding with hemorrhagic shock and retroperitoneal hematomas [ 10 , 11 ]. Hollow-point bullet ballistic characteristics are also associated with multiple full-thickness gunshot defects to the colon wall, whereas single defect of the colon wall is uncommon [ 8 , 12 ].…”

Modeling of wound ballistics in biological tissues simulators

“…The active phase of russia's war against Ukraine is demonstrated new challenges to military surgeons because of the high incidence of severe gunshot wounds due to the frequent application of high-energy weapons as well as modified bullets [2,3]. Our experience from the patient's management during russia's invasion showed some specific features of such gunshot wounds such as severe functional 23/ Том XXVIII / 1 disorders, an increased frequency of complications, and a high mortality rate [3,4,5,6,7,8,9].…”

“…The analyses of the published series allow us to plan and perform a mathematic simulation of the formation of wound canals in ballistic plasticine with a 5.45 mm 7N6M bullet and a 5.45 mm V-max expansive bullet as shown in previous studies, including forensic investigations and applications of numerical modeling simulation engineering systems namely Ansys Explicit Dynamics/Ls-Dyna [7,11,28].…”

Gunshot bullet trauma of the colon in combat patients injured in hybrid period of Russian-Ukrainian war during 2014-2020

“…Such ballistics might be associated with severe abdominal trauma: multiorgan injury, multiple perforations of the bowel with massive fecal diversion as well as a high risk of bleeding with hemorrhagic shock and retroperitoneal hematomas (9,10). Also, hollow-point bullet ballistic characteristics are also associated with penetrating, but not perforating injury (7,11).…”