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Traumatic injuries from civilian gunshot injuries represent a significant clinical burden to orthopaedic surgeons worldwide. Furthermore, the incidence of such injuries is increasing. Having a sound understanding of the pathophysiology associated with gunshot injuries and the appropriate management algorithm is vital. This chapter aims to review the current evidence regarding the incidence and prevalence of civilian ballistic trauma, the pathophysiological processes associated with these injuries, and the recommended management from emergent care at the time of injury to definitive surgery and rehabilitation. [ABSTRACT FROM AUTHOR]

The wounding potential of a projectile depends on its kinetic energy. The aim of the study was to investigate the deceleration of non-deforming full metal jacket handgun bullets (FMJ) in gelatine blocks of increasing length. The temporary cavity (TC) was visualized using a SA-X2 Photron camera. 126 test shots in 9 mm nominal calibre were fired under strict temperature control conditions (4°C) at small gelatine blocks ranging from 2 to 12 cm in length. The deposited energy was calculated based on the loss of bullet velocity through high-speed video analysis. The length of the TC was measured, when the TC reached its maximum height. The volume of the TC was approximated by a cylinder. Regression analysis showed a linear correlation between the length of the bullet path and the energy transfer. The constant deceleration of the FMJ bullets in gelatine up to 12 cm bullet path was confirmed across various brands and velocity ranges (270–450 m/s). Higher impact velocities correlated with increased loss of energy in the target medium. The shape of the bullet tip influenced the characteristic of deceleration. The volume of the tubular temporary cavity, derived from high-speed video records, was found to be proportional to the energy transferred. The proposed approach might be a valuable tool in advancing wound ballistics research. • Deceleration of FMJ bullets proportional to bullet path in compact target models. • Higher impact velocities resulted in greater loss of energy in the target medium. • The shape of the bullet tip influenced the characteristic of deceleration. • Proportionality of the temporary cavity to the transferred energy. [ABSTRACT FROM AUTHOR]

• Thermal modification does not significantly change the ballistic performance of coastal western hemlock CLT. • Density and hardness do no fully encompass the energy absorbing capacity of CLT under small arms ballistic threats. • Empirically fit UFC partial penetration equation formulations fit treatment specific datasets with minimal error. • One global UFC partial penetration equation can be utilized for design with an appropriate safety factor. To test and understand the potential for integration of thermally modified coastal western hemlock CLT systems in military applications, 109 ballistic experiments were conducted at the United States Army Engineer Research Development Center's Fragmentation Simulation Facility. For a range of CLT thicknesses, the depth of penetration and residual velocities were recorded for different striking velocities utilizing a 0.50 caliber steel sphere projectile. This information was used to compare and add to the existing ballistics data for CLT, investigate the effects of thermal modification on high strain rate loading of wood, assess physics-based empirical design equations used by the Unified Facilities Criteria, and evaluate energy absorbing behavior at a range of thicknesses and striking velocities. The experimental results showed that thermal modification does not significantly alter the full and partial penetration performance of coastal western hemlock CLT. However, the mechanism of fracture along the path of the projectile differed, which indicates that the model parameters used in the UFC design equation (density, hardness, and projectile properties) may not fully encompass the ballistic failure mechanisms of CLT. [ABSTRACT FROM AUTHOR]

The insufficient recognition of injuries by the BB-gun (regarded as toys for children) has led to its increasing misuse without permission, which has caused many public safety issues. Aiming to enhance the understanding of the injuries by the BB-gun, the experimental and numerical study of BB-Gun pellet penetrating "cowhide + gelatine" composite target was comprehensively carried out. It was confirmed from the experiment that BB-Gun is capable of inflicting severe or fatal wounds to important organs, and perforating the skin or not could be employed to evaluate the safety of BB-guns. Moreover, three forms of ballistic limit (including: velocity, kinetic energy and specific kinetic energy) of typical BB were calculated and analyzed by reasonably validated numerical simulation method. Additionally, a formulation was acquired by dimensional analysis based on the simulation results and was verified to accurately predict the ballistic limit velocity of BB with different mechanical properties. The method may help to improve the understanding on the minimal velocity needed to perforate skin and may be advised as the determination of the safety of BB-gun. [ABSTRACT FROM AUTHOR]

In this paper, the effect of the chemical composition of .22LR bullets was studied and correlated to the extent and quality of the markings left after shooting them with the same gun. Scanning electron microscopy and optical comparator microscopy equipped with 3D and profilometry modules were used as non destructive techniques with two main purposes. The first is to assist the firearm examiner in the choice of the ammunition most suitable for preparing the test bullets. The second is to propose an approach, crossing data from optical microscopy, profilometry and space-resolved chemical analysis, for explaining the morphology of striae, whether continuous or interrupted. Among the most notable results is the finding that commercial .22LR ammunition show very wide interbrand, interlot and intralot variability. A selection of test ammunition solely based on the same brand and model used on the crime scene is therefore not suitable, urging the need for a more accurate choice, based on a preliminary chemical analysis. [ABSTRACT FROM AUTHOR]

Synthetic models, also called "surrogates", are commonly used in wound ballistics in order to simulate human tissues. Despite several surrogates are worldwide accepted and used; some of them have not been yet fully validated and their limits for forensic reconstructions have not been deeply investigated yet. In this work we present a homicide/suicide case involving three gunshots to the head with bullets retained in the skull or beneath the scalp. Reconstruction of these cases was performed preparing three individual synthetic head models based on post-mortem computed tomography (PMCT) measurements. Ballistic soap, polyurethane plates and 10% ballistic gelatine at 4°C were used as simulants in individually adapted thickness. Ballistic tests were performed using the questioned firearm and ammunition type. The damages on the synthetic models have been compared to the findings in PMCT and autopsy of the victims. Although the results highlighted general similarities in terms of injury characteristics, some of the experimental shots overpenetrated. Furthermore, the bullets recovered in the synthetic models did not show the same quality of deformations as the questioned bullets. This lack of bullet deformation in the synthetic models might be mainly attributed to the physical difference between real bones and polyurethane surrogate. [ABSTRACT FROM AUTHOR]

Gun violence is a global phenomenon with regional variation in frequency and severity. Handguns are often used in violent deaths such as suicides and homicides. Hence, ballistic trauma is a critical subject of forensic investigations. Trauma patterns are fundamental evidence for the reconstruction of the incident and for the determination of the manner of death. This study investigated the differences in trauma patterns with a series of experiments using six different calibers (.22 LR, .38 Special, .380 ACP, 9×19mm, .40 S&W, and .45 ACP) and four different bullet types. Synbone® spheres (polyurethane bone proxies) were used for close range 30cm simulated executions. The polyurethane spheres constitute an excellent proxy for human crania at the macroscopic level as suggested by other studies. The results showed that the radius of the entrance wound is positively correlated (Pearson's correlation coefficient R=0.846, p<0.05) with the caliber dimension. As muzzle velocity increased, endocranial beveling increased. Bullet weight, conversely, does not seem to have an effect on the size of the endocranial beveling present in Synbone® spheres. The ballistic experiments exhibited similarities in entrance wound morphology; radial and concentric fracture patterns, hydraulic burst effect, circumferential delamination, and endocranial beveling with that of documented forensic cases with corresponding caliber shot. Synbone spheres seem appropriate for ballistic simulations of cranial injuries; yet, more research is needed to verify these observations. [ABSTRACT FROM AUTHOR]

Ballistics is the study of a projectiles motion and can be broken down into four stages: internal, intermediate, external and terminal ballistics. The study of the effects a projectile has on a living tissue is referred to as wound ballistics and falls within terminal ballistics. To understand the effects a projectile has on living tissues the mechanisms of wounding need to be understood. These include the permanent and temporary cavities, energy, yawing, tumbling and fragmenting. Much ballistics research has been conducted including using cadavers, animal models and simulants such as ballistics ordnance gelatine. Further research is being conducted into developing anatomical, 3D, experimental and computational models. However, these models need to accurately represent the human body and its heterogeneous nature which involves understanding the biomechanical properties of the different tissues and organs. Further research is needed to accurately represent the human tissues with simulants and is slowly being conducted. [ABSTRACT FROM AUTHOR]

• A mole gun can be diverted from its classic use to become a homemade firearm. • The use of this homemade firearm has caused serious intracorporeal injuries. • The ballistic analysis of homemade firearms is essential for understanding the facts. The body of a man was found in a workshop at the back of his home, a metal pipe embedded in his chest. In the immediate vicinity of the body, among various tools, was a machine containing a holster hit of lead shot evoking a mole-trap-type "taupe gun" (mole gun). The findings at the scene and the presence of a metal tube, sinkers, and a flock in the chest are in favour of the use of a homemade firearm. The autopsy and CT scan revealed atypical ballistic thoracic trauma responsible for a dilaceration of both the heart and thoracic aorta that caused the death. The autopsy also found a contused wound at the back of the skull without intracranial lesion, which may be due to the fall of the victim after the thoracic trauma. There is no other traumatic lesion and in particular no lesion of seizure, constraint, or defense. Toxicological analyses revealed the presence of alcoholic impregnation at the time of death. These findings, confronted with the expertise of a balistician, made it possible to understand how the victim used a mole gun to cause these lesions. A metal tube was used as a cannon to aim more surely at the heart but also as a means of triggering the propulsion mechanism of the trap without having to stretch out the arm. The tube, thinner than the barrel, had disengaged from its tip to be embedded with the lead shot in the chest of the victim. [ABSTRACT FROM AUTHOR]

Introduction: Surgical treatment of high-energy gun-shot wounds (GSWs) to the extremities is challenging. Recent surgical doctrine states that wound tracts from high-energy GSWs should be laid open, however the experience from previous conflicts suggests that some of these injuries can be managed more conservatively. The aim of this study is to firstly characterise the GSW injuries sustained by UK forces, and secondly test the hypothesis that the likely severity of GSWs can be predicted by features of the wound.Methods: The UK Military trauma registry was searched for cases injured by GSW in the five years between 01 January 2009 and 31 December 2013: only UK personnel were included. Clinical notes and radiographs were then reviewed. Features associated with energy transfer in extremity wounds in survivors were further examined with number of wound debridements used as a surrogate marker of wound severity.Results: There were 450 cases who met the inclusion criteria. 96 (21%) were fatally injured, with 354 (79%) surviving their injuries. Casualties in the fatality group had a median New Injury Severity Score (NISS) of 75 (IQR 75-75), while the median NISS of the survivors was 12 (IQR 4-48) with 10 survivors having a NISS of 75. In survivors the limbs were most commonly injured (56%). 'Through and through' wounds, where the bullet passes intact through the body, were strongly associated with less requirement for debridement (p<0.0001). When a bullet fragmented there was a significant association with a requirement for a greater number of wound debridements (p=0.0002), as there was if a bullet fractured a bone (p=0.0006).Conclusions: More complex wounds, as indicated by the requirement for repeated debridements, are associated with injuries where the bullet does not pass straight through the body, or where a bone is fractured. Gunshot wounds should be assessed according to the likely energy transferred, extremity wounds without features of high energy transfer do not require extensive exploration. [ABSTRACT FROM AUTHOR]

Based on its intrinsic mass and velocity, a bullet has an upper limit of wounding potential. Actual wound severity is a function of the bullet construction and trajectory, as well as the properties of the tissues traversed. Interpreting physicians must evaluate the bullet trajectory and describe patterns of injury resulting from the effect of energy transfer from the projectile into living tissue. A basic understanding of firearms, projectiles, and wound ballistics can help the interpreting physicians in conceptualizing these injuries and interpreting these cases. [ABSTRACT FROM AUTHOR]

Abstract: For competitors in the shooting sports, gun recoil can affect performance and create discomfort. An objective method of measuring felt recoil forces would be useful to evaluate methods of recoil reduction. An experimental test apparatus was developed to measure recoil forces of sporting rifles and shotguns. No modifications to the firearms themselves were necessary to make the measurements. Through both inertial and dissipative restraint mechanisms, the apparatus reproduced gun movement that was representative of that experienced by a particular shooter. This should result in measured recoil forces similar to those experienced by the shooter. The apparatus measures the horizontal shoulder force and the vertical force component exerted at the stock comb. The recoil event was found to be quite short, having duration on the order of 10ms. Peak recoil forces for common shotgun target loads were in the range of 1.6–2.2kN (360–494lbf). The apparatus was found sensitive enough to measure recoil force differences among different factory loaded ammunition, and differences in recoil force imparted by different firearms shooting the same ammunition. The apparatus should prove useful for quantifying differences in felt recoil as affected by ammunition type, gunstock geometry, barrel porting, recoil reduction devices, and gun weight, among other factors. [Copyright &y& Elsevier]

Abstract: Greenhill''s Rule for estimating rifling twist in artillery and small arms is interesting both because of its simplicity and longevity. This article describes (a) Greenhill''s Simplified Rule for estimating the twist of rifling; (b) describes his original, more complete, but much less known Rule; (c) summarizes how he got the Rule; and (d) relates it to the modern stability factor. Some comments about twist, bullet stability, and black powder velocities are presented. [Copyright &y& Elsevier]

• Small and medium arms fire can be stopped with a snow-based protective structure. • Snow-filled commercial gabions can be efficiently constructed. • Structures can be construction at a rate of about 0.5 hr/m3 with common equipment. • Snow set-up time of 24 h is recommended. • All but one model of projectile penetration in snow matched our results within 32%. Small (5.56 mm, 7.62 mm and 9 mm) and medium (12.7 mm) arms rounds were fired at snow-filled 1.5m cubic gabions in a mid-winter condition in Fairbanks, Alaska. The rounds were excavated and penetration by each ammunition type was measured. A distribution and average of penetration depth was determined. All 320 rounds fired were captured within 1.5m after entering the snow barrier. Comparison with published models of ballistics penetration of snow showed mixed results with several matching our data within 10% and all but one within 32%. However, most of these models are simplistic in that they accommodate limited variables and therefore may not be expected to perform well in all settings. We conclude that snow-based ballistics protection structures can be quickly and efficiently erected in suitable environments and with minimal size, can provide reliable protection against small and medium arms fire. [ABSTRACT FROM AUTHOR]

Evaluation of cartridge cases is essential within forensic ballistic analysis and is used in an attempt to establish a connection to the weapon used to fire it. This study consists of two experiments. The aims of Experiment 1 were to establish whether micro-CT is appropriate and repeatable for ballistic cartridge case analysis and if measurements can be extracted repeatably and reliably. Experiment 2 aimed to compare cartridge cases from two weapons to establish the magnitude of variation within and between weapons. A total of 48 cartridge cases fired by two distinct weapons were collected and micro-CT scanned to a high resolution. One randomly selected cartridge was scanned ten times under the same conditions to ensure repeatability of the scanning conditions in Experiment 1. Three novel measurements to quantitatively assess the firing pin impressions were proposed in Experiment 1 and comparatively analysed from two weapons in Experiment 2. Experiment 1 showed that micro-CT is an effective and highly repeatable and reliable method for 3-dimensional imaging and measurement of ballistic cartridge cases. Furthermore, high agreement for inter-rater reliability was found between five raters. Quantitative micro-CT analysis of the firing pin impression measurements in Experiment 2 showed a significant difference between the two studied weapons using Welch's t-test (p < 0.01). This study shows the advantage and reliability of utilising micro-CT for firing pin impression analysis. Quantitation of the firing pin impression allows distinction between the weapons studied. With expansion to further weapons, application of this methodology could complement current analysis techniques through classification models. [ABSTRACT FROM AUTHOR]

Bullet ricochet off a surface in a shooting scene occurs in diverse conditions and affected by array of factors. Therefore ricochet analysis of a particular incident demands case by case analysis supported by the knowledge of existing subject knowledge and empirical testing. In this view, existing empirical test results on bullet ricochet experiments have become always assisted and referred by investigators during scene reconstruction and in Courts. This forensic based research was aimed to understand the ricochet behaviour and related aspects of Kalashnikov bullets (7.62mm×39mm) on 1mm sheet metal. 1mm sheet metal was selected as the target surface of the study, based on its greater possibility of existing in concurrent urban environments as vehicle bodies, electrical appliances, road signs, boundary walls, partitions, walls of mobile houses etc. The research added brand new knowledge to the firearm investigation field in general and specifically to AK shooting investigations and scene reconstruction. The ricochet angles and critical angle of 1mm sheet metal and AK bullets, relationship of different impact feathers and angle of incidences are some of the main findings of the research. The double head impact mark which produces as a result of bullet's interaction with the target and it's specific relationships with the incident angles is the other most important results of the research which has not reported so far in a bullet ricochet study. In addition to the contribution of knowledge to the field of forensic sciences in general and forensic ballistic in particular, this research further emphasises the need for case by case empirical study to understand the ricochet behaviour of different bullet and target combinations. On the other hand, this study very deeply convinced firearms investigators on the risk of applying general bullet ricochet theory on yielding and nonyielding surfaces to reconstruct all bullet ricochet incidents which would result in wrong interpretations, critical errors in shooting scene reconstruction and finally for false testimonies. [ABSTRACT FROM AUTHOR]