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The discovery of a specific form of Late Neolithic object in northeast Poland, commonly interpreted as reed arrowshaft straighteners, prompted investigation into the possible use of reed for archery in the European past. To examine the archery qualities of this raw material, and thus the likely rationale behind the manufacture and use of reed arrowshafts, a number of mechanical and experimental analyses were conducted. The results presented here indicate that reed was well suited for prehistoric archery. This is demonstrated above all by the arrowshaft stiffness required by this discipline, defined as the spine‐force, but also both the technological ease of production of arrows and their ballistic capabilities. [ABSTRACT FROM AUTHOR]

In examining deaths resulting from gunshot wounds, it is important to describe the wound pathway created by the projectile. Forensic pathologists must identify all entrance and exit wounds and account for all projectiles. Occasionally, confusion arises as to whether a skin defect represents an entrance wound or not, an exit wound, or some other type of wound. Herein, we propose the descriptor "bullet track skin defect" as a formal description for a superficial skin defect created along the pathway of a projectile within the body. Specifically, we define the "bullet track skin defect" as a partial‐ or full‐thickness skin defect produced by a projectile traveling beneath the skin in a relatively tangential fashion as part of a wound pathway within the body. It is somewhat analogous to a traditional graze or superficial tangential wound, wherein the projectile traveling outside the body strikes the skin tangentially from above, without entering the body. However, the projectile is already traveling within the body with the bullet track skin defect, disrupting the skin tangentially from below rather than from above, without exiting the body. Although these defects are not a common presentation of gunshot wounds, they are certainly not rare. With this case series, we suggest that such defects may be referred to as "bullet track skin defects." Alternative language that can substitute for "bullet track skin defects" includes "bullet track skin wounds" or "bullet track cutaneous defects." [ABSTRACT FROM AUTHOR]

This review covers the effect of ageing on solid gun and rocket propellants in terms of their ballistic properties. A brief overview of the types of methods, which can be used to determine such parameters, is provided and the literature is described in terms of broad motivation areas for the research. It has been demonstrated that understanding the effects and outputs of propellants, and how these might be affected by ageing, remains an important area of research in the field of energetic materials. [ABSTRACT FROM AUTHOR]

Researchers use a variety of target materials, and sometimes combinations of materials, in their archaeological experiments to examine thrust‐spear or projectile penetration, impact angle, durability, and other issues involving prehistoric hunting weaponry. This variety of target materials is beneficial to archaeological science in several ways, but it may also hinder the comparison of results because many of these target materials do not necessarily share similar physical properties. Here, we assess the penetration properties of four different target materials—store‐bought meat, clay, and two types of gelatin—via static penetration tests of a modern broadhead‐tipped arrow and a stone‐tipped projectile attached to an Instron Universal Materials Tester. Our analyses of load‐deflection curves, peak load, and work energy demonstrate how the four target materials are similar in some ways but different in others, which suggests that researchers may strategically employ one or several depending on the question asked or hypothesis tested. [ABSTRACT FROM AUTHOR]

Interior ballistics modelling intends to calculate physical quantities by solving equations requiring a set of input like thermodynamical properties linked to propellant or mechanical properties like friction coefficients, linked to the system, that are often difficult to assess experimentally. Using a consequent and high‐quality dataset of thousands of 155 mm modular charge experiments, we investigated how deep and machine learning approaches could build an efficient model for predicting muzzle velocity, pressure, and ignition time. After identifying the main variables influencing the physics and several potentially relevant to the machine learning and deep learning algorithms, a stacking ensemble learning model (SEL) was built. It is composed of eight machine learning algorithms and one deep learning algorithm, all as weak learner, reaching a consensus for predicting experimental outputs through a strong learner. The performance assessment, on a 900 experiments test data set that were not used in training, shows a prediction accuracy of 97 % at 1 % accuracy for muzzle velocity, 93 % at 3 % for pressure and 72 % at 5 ms for ignition time. The prediction ability for muzzle velocity within 2 m/s reaches 73 % that can be considered as sufficient. Furthermore, the SEL model even having zero knowledge about physics can discriminate gun barrel erosion effect at high and low pressure. This approach allows to imagine a way of modelling physical phenomena poorly described by physical equations or requiring unmeasurable figures. [ABSTRACT FROM AUTHOR]

Empirical assessment of cetacean welfare to inform stranding interventions is lacking. Here, potential welfare indicators are described for two stranded pygmy killer whales (Feresa attenuata), along with euthanasia procedures and pathology of potential relevance. The animals were filmed for 3.5 and 1.5 hr, respectively, allowing assessment of 19 indicators, including animal behaviors and human interventions. Eight interventions and 19 animal behaviors were identified; 17 and 11 behaviors were displayed by animal 1 and 2, respectively. Examination of ballistics euthanasia revealed atypical projectile placement and characterized animal behavioral responses, but welfare implications could not be assessed as insensibility was not verified in-field. Pulmonary edema and renal degeneration were documented in both animals; differential etiologies include ischemia-reperfusion, shock, and/or myopathy. Potential relationships among histopathology and welfare indicators are explored to infer affective experiences. For example, simultaneous head-lifting with respiration increased over time which, alongside pulmonary edema, suggests these animals experienced breathlessness. Other likely affective states include fatigue and discomfort; there are insufficient data to estimate the intensity or duration of these experiences or to provide an overall welfare grade/score. Further data are required to validate the proposed welfare indicators and to progress development of holistic approaches to welfare assessment at cetacean strandings. [ABSTRACT FROM AUTHOR]

An interval optimization method considering tolerance design is proposed to solve the uncertainty optimization problem of interior ballistics of cased telescoped ammunition. Firstly, the interval optimization model of the interior ballistics of the cased telescoped ammunition considering tolerance design is constructed. The interval optimization model of the interior ballistics of the cased telescoped ammunition considering tolerance design under uncertainty is presented. Then, considering the extremely low computational efficiency of the interval uncertain optimization, the back propagation neural network surrogate model is introduced. A series of pareto optimal solution is obtained by using non‐dominated sorting genetic algorithm II. Through the given design scheme, it provides a reference for the optimization of the interior ballistic performance of the cased telescoped ammunition under uncertain condition. [ABSTRACT FROM AUTHOR]

One of the most significant challenges in designing a hyper‐firing‐rate weapon is to balance the interior ballistics behaviors of a multi‐projectile system. This paper proposes a multi‐projectile system with a front nozzle to correct interior ballistic characteristics based on rarefaction wave theory. Firstly, a two‐dimensional two‐phase flow model for the hyper‐firing‐rate weapon is established. Then the application to a standard virtual gun as a benchmark for interior ballistic codes is used to validate the accuracy. In addition, the interior ballistics behaviors of the three‐projectile system without and with the front nozzle are investigated. Finally, the interior ballistics behaviors of the three‐projectile system are corrected by changing the open time of the front nozzle. The results show that the new correction method for the multi‐projectile system reduces the recoil and the pressure while balancing the muzzle velocity. The finding guides future ballistic research on the multi‐projectile system. [ABSTRACT FROM AUTHOR]

The balancing force of the interior ballistics is an important issue in the design of the recoilless gun. It has been found in practice that the balancing force design method for recoilless guns based on the traditional classical interior ballistic theory cannot guide the balance from the physical mechanism and process. In order to study the unbalanced force experienced by the recoilless gun during the firing of the projectile and the variation law of its various parameters with time, the analysis and calculation method of the balanced interior ballistics is proposed in this article. This method separately models the aerodynamic and propellant combustion processes of the recoilless gun, using the characteristic line method to solve the model numerically. This method can be used to predict the change of the unbalanced force acting on the recoilless gun during the projectile firing of the recoilless gun. The reliability of the algorithm is verified by the interior ballistic performance when China 78 type 82 mm recoilless smoothbore gun launches the projectile. The study found that the unbalance impulse generated by the gas inside the barrel fired by the recoilless gun accounts for only 1.5 % of the total recoil impulse, but it has a great influence on the amount of impulse a shooter has can take. This approach provides a better understanding of this complex internal ballistic process, which has important implications for the design and improvements of recoilless guns. [ABSTRACT FROM AUTHOR]

Solid rocket motors are used for both national defense and launch vehicles. The internal ballistics of the motor depend on the propellant burning rate, which is often modified by burning rate enhancers. Despite the common use, there is not a complete mechanistic understanding of how these modifiers influence the combustion process. In this comment, it is argued that these additives can influence propellant combustion as a catalyst, via thermodynamic means, or a combination. An approach is suggested on how to classify traditional and novel burning rate modifiers as a first step to improving the scientific community's knowledge on the matter. [ABSTRACT FROM AUTHOR]

Soot is deposited from 20–30 cm from the muzzle of most handguns and arranged concentrically around the entry wound. We examined a case of a self‐inflicted gunshot wound from a 9‐mm pistol that left an unusual pattern of soot deposition consisting of two circular 3‐mm deposits of soot located 2 cm from the entry wound. Examination of the weapon and test‐firing it against a cloth reproduced the soot deposits, which were caused by two ports on the top of the barrel. Examination of the weapon and comparing the barrel with the entry wound and surrounding skin may provide important information about the type of weapon, the muzzle‐to‐target distance, and atypical soot deposits. [ABSTRACT FROM AUTHOR]

Rarefaction wave gun can significantly reduce the recoil and the barrel heat without affecting projectile velocity during the launching process. This paper aims to improve the understanding of the muzzle flow characteristics during a rarefaction wave gun firing and clarify the different ballistic behaviors between the rarefaction wave gun and the traditional gun. First, the mathematical models and the numerical methods of the muzzle flow with the interior ballistic process were established. Then, the numerical simulation results were compared with the experimental data to validate the reliability and accuracy. Next, the rarefaction wave propagation behavior was described, and the interior ballistic process of the rarefaction wave gun was compared with that of the traditional gun. Then the development law of the muzzle flow field for the rarefaction wave gun coupled with the interior ballistics process was studied. Finally, the different detailed results of the muzzle flow between the traditional gun and the rarefaction wave gun were investigated. The development processes of the muzzle flow in both guns are generally similar, but the strength of the main flow parameters and the ballistic performances for the rarefaction wave gun are smaller than that for the traditional gun due to the rarefaction wave influence. This paper could provide a valuable reference for the research and design on the rarefaction wave gun. [ABSTRACT FROM AUTHOR]

The above article, published online on 07 February 2023 in Wiley Online Library (wileyonlinelibrary.com) has been retracted by agreement between the authors, the journal Editors, Randall L. Simpson, Wilhelm Eckl, Richard Gee, the International Pyrotechnics Society, and Wiley‐VCH GmbH. The retraction has been agreed due to the corresponding author reaching out to the editorial office to retract the article as they have discovered major data analysis errors that invalidate the conclusions of the paper. The author deeply apologizes for this mistake. [Extracted from the article]

Assessment of wound characteristics and the identification of various constituents of firearm discharge at autopsy play a key role in the determination of range of fire. In relation to wounds caused by shotguns, identification of the wad within the wound track, or of injury caused by the wad, is typically thought to suggest a fairly close range of fire. We present a case of a fatality due to a shotgun slug wound where the presence of the wad within the decedent's body was proposed by defense at criminal trial to favor accidental close range discharge during a struggle for the weapon—as opposed to the prosecution's contention of intentional firing of the weapon from a greater range and through an intermediate target. We undertook test firing of a shotgun of similar design to that which was fired during the interaction (a 12‐gauge pump‐action shotgun) using shotshells consistent with the slug that was recovered from the body (Winchester Super X brand), which demonstrated that the non‐attached fiber wad present in this shotshell design can accompany the slug over distances of at least up to 22 feet (6.7 m) and even after transit through intermediate targets such as a vehicle headrest. These novel data provide assistance with estimation of range of fire in instances of injuries caused by shotgun slugs. [ABSTRACT FROM AUTHOR]

It is important to know the process of hot spot creation to improve the safety of working with melted TNT. One of the probabilities is the air bubbles in TNT that melted during the firing and internal ballistics, which are the results of casting problems. Thus, in this paper, the accuracy of this probability was studied. Melted TNT is a highly viscous fluid, so in this study by improving the numerical code, the effects of the temperature‐dependent physical properties have been seen in the calculations. The results show that the viscosity work makes the bubble heated and rises, its temperature in comparison with the fluid environment. But the variations are a maximum of 4 °K. Therefore, it seems that the studied factors in this paper can′t be the reason for melted TNT undesirable ignition. [ABSTRACT FROM AUTHOR]

A "plated bullet" has a thin layer of electroplated metal covering the lead core of the projectile. In certain situations, this thin layer of electroplated metal can fracture upon discharge of the firearm. When such fracturing occurs, vaporous lead can escape through the fracture lines of the spinning projectile, resulting in a spiral‐shaped deposition of dark residue surrounding a central bullet defect. The spiral‐shaped pattern is referred to as "comet‐tailing," or the "vortex effect." In this report, three homicide cases with associated comet‐tailing are presented. Police, death investigators, and forensic pathologists should be aware of this unique finding. [ABSTRACT FROM AUTHOR]

Black powder weapons are rarely used in countries where access to firearms is easy. Poland has a fairly restrictive law regarding possession of firearms but under the Weapons and Munitions Act of May 21, 1999, as further amended, the possession of black powder weapons using separate loaded ammunition and manufactured before 1885, or replicas thereof, is legal without a permit. When the amendment was introduced, forensic pathologists anticipated a rush of cases involving such weapons, mainly suicides, but also accidents and homicides, but in our own practice in Lodz over the past 10 years (2010–2019) we have encountered only 7 such cases. Although the number is not particularly high, it does nevertheless account for nearly one‐fifth of all gunshot deaths in the area. The aim of this paper is to present a series of deaths involving the use of black powder handguns. In analyzed cases, the victims were mostly men, they were sober, and their manner of death was suicide. As far as age was concerned, no regularity was found. All black powder handgun shots were characteristic enough in comparison with those from conventional firearms that they could be identified easily—the entrance wounds were larger than usual, there was a lot of gunpowder around them and in the wound canal, the bone fractures were extensive. Analysis of the literature and of our own material indicates that easy availability is not the only factor affecting the choice of a weapon; ease of use and reliability are also important. [ABSTRACT FROM AUTHOR]

The impingement of muzzle blast wave is an important engineering problem and has been widely discussed for decades. The problem becomes more complex when the cannon shots at a high frequency. An accumulation phenomenon of the impingement of multiple blast waves is observed. In this research, the numerical study on impinging flows, which are generated by the propellant gas released from the muzzle of a high‐frequency launch system, is achieved. The interior ballistics model is employed in the simulation of muzzle flow. In order to have insight into the effect of continuous impingement, three cases with different launch frequencies are studied and compared. Under the computational load of muzzle flow impingement, the dynamic response of monitoring equipment is discussed based on an elastic mechanics model, and the contribution of the impinging frequency to the damaging effect is analyzed. It can be concluded that the frequency of the muzzle flow impingement has an important influence on the damaging effect. Furthermore, the accumulation of impingement depends on the shooting frequency and the intensity of each impingement. [ABSTRACT FROM AUTHOR]

Ammunition designers are faced now a day with the tasks of improving muzzle velocity (MV) to achieve required penetration as well as developing gun propellant with minimum variation of ballistics at extremes of temperatures so as to maintain safe chamber pressure of gun. In order to meet the requirement an optimized propellant composition containing RDX, energetic plasticizer, nitrocellulose (NC), cellulose acetate (CA) and additives referred as Enhanced Energy Propellant (EEP) was processed and evaluated theoretically and experimentally. Performance in respect of ballistic parameters (static and dynamic), sensitivity, thermal characteristics, thermal stability and mechanical properties were evaluated and compared with that of the conventional triple base propellant (TBP). Experimental data on comparative study indicated that the newly developed EEP is superior to existing TBP in terms of energy, stability and thermal properties while sustaining the safe chamber pressure of gun. Dynamic firing results show that, EEP requires lower charge mass (7.43 kg) and lesser chamber pressure (459 MPa) to realize MV at par with standard. This illustrates high energy of EEP. [ABSTRACT FROM AUTHOR]

With three‐dimensional (3D) laser scanning technology and software packages, the practice of documenting and measuring bullet trajectories has benefited from greater accuracy and reproducibility. This study investigated the accuracy and reproducibility of the bullet trajectory tools in the software package, FARO Zone 3D (FZ3D). Twelve participants were provided laser scanner data for 21 bullet trajectories on drywall panels with impact angles between 25° and 90°. When the impact plane was manually aligned by the operator, 75% of the absolute errors were within 0.91° and 0.98° for the azimuth and vertical angles, respectively. The vertical angle improved to 0.47° when impact plane alignment was taken with respect to gravity (no operator influence). Thus, manual alignment is shown to be subject to greater error than alignment with gravity. However, this study shows that the accuracy and reproducibility of the FZ3D bullet trajectory tools to be comparable with previous research studies. [ABSTRACT FROM AUTHOR]

The susceptibility for recreational shooters to transfer gunshot residue (GSR) to both the interior and exterior of a vehicle is investigated. A comprehensive sampling protocol was used to assess the most likely areas of GSR transfer from recreational shooter contact, such as the steering wheel and the area, the firearms were stored (the trunk). Up to 315 characteristic GSR, particles were found in several locations throughout the interior of a vehicle. As many as 876 characteristic particles were found throughout a single vehicle. The data indicate that vehicles frequently occupied by firearms users are a potential source for inadvertent transfer of GSR to persons unrelated to firearm activity. In criminal cases where vehicles have been used, such transfer processes for GSR need to be considered within the context of any case interpretation. The implications for subsequent contamination and transfer processes from such vehicles require further investigation. [ABSTRACT FROM AUTHOR]

In this study, a new method based on regularised orthogonal matching pursuit (ROMP) decomposition is proposed to extract the feature of the ballistic target's rotating micro-motion. Based on the establishment of the ballistic target rotation model, the general model of target's narrowband radar echo is obtained. An over-complete dictionary of atoms is established by combining the intrinsic characteristics of the signal model, and the selection of the matched atoms is carried out according to the regularisation principle. The extraction of the target's rotating micro-motion feature and the reconstruction of the original signal are realised. Simulation results show that the method can extract the micro-motion feature efficiently and accurately. [ABSTRACT FROM AUTHOR]

In order to assess the efficacy of vacuum metal deposition (VMD) as a technique to develop fingermarks on ballistic metallic surfaces, a preliminary study using six donors (three male & three female) was conducted. Using a sequential metal deposition process, two metal combinations were studied—gold/zinc and silver/zinc. Results indicate the potential of this technique, by developing identifiable fingermarks on brass metal disks aged from a few days up to more than a month old. As the development of fingermarks on fired (brass) cartridge cases is an area of interest, a further study was conducted where a total of 20 fingermarks were deposited on cases. After firing, second level fingermark characteristics were successfully observed on cartridge cases highlighting its potential as a fingermark enhancement method for ballistic brass materials. Further work is required to fully evaluate the VMD process and its reliability as a fingermark enhancing method on ballistic surfaces. [ABSTRACT FROM AUTHOR]

The appearance of new projectile propulsion modes is viewed as an important element for understanding human behaviour during the Palaeolithic. Because the organic components of hunting weapons (the bow, spear‐thrower and arrow, and spear shaft) are only rarely preserved archaeologically, some effort has been invested in experiments to explore how the projecting modes could be identified through the analysis of stone points. The kinetic energy developed by each mode of propulsion has been considered a key variable in these experiments. However, the data used in these studies generally come from a few ballistic studies, with varied results. We present the results of a systematic study conducted with a ballistic pendulum and combined with a classic ballistic analysis. We quantified and compared the kinetic energy developed by the four standard modes of propulsion known for the Palaeolithic. The kinetic energy values that we attained, especially those measured for thrusting spears, clearly differ from what has been assumed up to now, and thus challenge current models on the evolution of hunting technology. [ABSTRACT FROM AUTHOR]

Studies on ballistic trauma to the ribs and thorax, cranium, and long bones demonstrate the potential of obtaining a bullet caliber from an entrance wound. In order to validate prior research on caliber estimation in bone tissue and assess the viability of bullet type determination based on the macroscopic evidence at the entrance wound, thirty fleshed pork (Sus scrofa) shoulders (humeri) were shot with either lead or copper jacketed bullets in one of three calibers; 0.22, 9 mm, or 0.38. Overall, our findings are consistent with previous research indicating that calibers can be grouped into "small" and "large" categories. Bullet type, lead or copper jacket, can be ascertained based on cortical flaking and the analysis of materials deposited around the entry wound. The addition of this evidence holds value in cases where no firearm or ballistic evidence is recovered from a crime scene. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: Microvascular free tissue transfer is often employed to reconstruct significant facial defects from ballistic injuries. Herein, we present our comparison of complications between self-inflicted and non-self-inflicted gunshot wounds after microvascular free tissue transfer.Study Design: Retrospective case review.Methods: Approval was obtained from the JPS institutional review board. We performed a retrospective review of cases of ballistic facial injuries between October 1997 and September 2017 that underwent vascularized free tissue transfer for reconstruction. Comparisons were made between self-inflicted and non-self-inflicted gunshot wounds after microvascular free tissue transfer. The χ2 test was used for all comparisons. P value and 95% confidence interval (CI) were reported.Results: There were 73 patients requiring free flap reconstruction after gunshot wounds to the face during the study period. There was a statistically significant difference in the rates of nonunion between self-inflicted and non-self-inflicted wounds (P = .02, 95% CI: 0.9 to 35.8) There were also no significant differences in flap failure (P = .10, 95% CI: -2.8 to 24.2), plate exposure (P = .28, 95% CI: -6.7 to 33.0), wound infection (P = .40, 95% CI: -8.9 to 31.2), scar contracture (P = .60, 95% CI: -8.1 to 25.1), and fistula formation (P = .13, 95% CI: -2.8 to 28.8) between patients with self-inflicted and those with non-self-inflicted wounds. Overall, complication rates were significantly higher in the self-inflicted group compared to the non-self-inflicted group (P < .0001, 95% CI: 32.6 to 68.6).Conclusions: Patients with self-inflicted injuries had more complications postoperatively than those with non-self-inflicted injuries. This is likely helpful in surgical planning and patient counseling.Level Of Evidence: 4 Laryngoscope, 129:837-840, 2019. [ABSTRACT FROM AUTHOR]

A bystander claimed to have been shot by a police officer, and CT scans were used to match qualitative and quantitative aspects of the unremoved bullet with police issued 9 mm Luger ammunition. CT scan methodology proved a valid approach for the measurement of bullets based on calculated measurement capability and correlation with "gold standard" physical measurement by vernier caliper. Measurements regarding length and base diameter, as well as length/diameter ratio, were insufficient to unambiguously identify a specific caliber, or a bullet of specific mass within a caliber class. It was, however, possible to exclude a bullet of specific design and mass with well‐characterized precision and accuracy values under selected CT scan conditions. A 9 mm Luger bullet (115 gr FMJ RN) was excluded from involvement in a shooting based on qualitative bullet shape combined with length, base, and ratio measurements of the bullet in‐situ for the victim. [ABSTRACT FROM AUTHOR]

Factors influencing effectiveness of automated comparisons, test‐fired bullets, and cartridge cases from 0.38 Special revolvers were logged into the Evofinder® Ballistic ID System. Tests were performed as follows: First test correlated test‐fires of the same type, second test compared different types of ammunition components, third test replicated the second test in a larger database, and fourth test replicated the third test with students having no previous firearm identification experience. System effectiveness with projectiles in the first test was 0.89. With cartridge cases, effectiveness was 0.79 with combined results, but analysis of separate results by breech face and firing pin revealed low effectiveness by breech face (0.40). In the second, third, and fourth tests, effectiveness with projectiles were 0.61, 0.51, and 0.44. In addition, these tests had effectiveness with cartridge cases equivalent to 0.55, 0.43, and 0.44. Results are useful to establish routine protocols, system improvements, or comparative assessment of other electronic systems. [ABSTRACT FROM AUTHOR]

Abstract: Three‐dimensional (3D) technologies contribute greatly to bullet trajectory analysis and shooting reconstruction. There are few papers which address the errors associated with utilizing laser scanning for bullet trajectory documentation. This study examined the accuracy and precision of laser scanning for documenting trajectory rods in drywall for angles between 25° and 90°. The inherent error range of 0.02°–2.10° was noted while the overall error for laser scanning ranged between 0.04° and 1.98°. The inter‐ and intraobserver errors for trajectory rod placement and virtual trajectory marking showed that the range of variation for rod placement was between 0.1°–1° in drywall and 0.05°–0.5° in plywood. Virtual trajectory marking accuracy tests showed that 75% of data values were below 0.91° and 0.61° on azimuth and vertical angles, respectively. In conclusion, many contributing factors affect bullet trajectory analysis, and the use of 3D technologies can aid in reduction of errors associated with documentation. [ABSTRACT FROM AUTHOR]

Abstract: In the present paper we report recommendations for safe handling with unknown explosive materials and compositions. These are based on quantum‐chemical evaluations of the detonation and ballistic profiles of newly synthesized explosives and their comparison with the known reference compounds. The proposed methodology is rather simple, fast and does not require special skills. Meanwhile, it allows an effective quenching of the potential risk associated with injuries caused by accidental explosions. Additionally, we have developed two utilities, which significantly simplify the calculation process. The proposed algorithm was found to be more successful in estimation of detonation velocity of several common explosives in comparison with commercially available software EMDB, EXPLO5 and Cheetah 8.0. The reported results will be useful for scientific personnel working in the field of development and testing of explosives. [ABSTRACT FROM AUTHOR]

Abstract: Ballistic gelatin as simulant of the human body and organs is a support in forensics. After having obtained very good results for a new gelatin‐based composite in terms of physicochemical and rheological properties, this study focused on this material's mechanical behavior during stabbing and shooting versus bovine and porcine organs and standard ballistic gelatin. The hybrid gelatin has a predominantly elastic behavior at 23°C, whereas the elastic modulus becomes practically constant in the 10–0.1 Hz frequency range. In terms of stabbing behavior, the small variations obtained between porcine organs and surrogate are below 5%, the perforation indicating a good similarity. From the ballistic test results using 10 × 28T rubber balls, it has been seen that the hybrid ballistic gelatin conducts to more reliable and reproducible values of perforation/penetration versus standard gelatin, making from it a real candidate for use in forensic tests. [ABSTRACT FROM AUTHOR]

A series of experiments and simulations were conducted to investigate the effects of hardness and toughness of ceramic on the ballistic performance of ceramic armour modules. The experiment was conducted using ceramics from 3M technical ceramic, using the tiles Grade T, T+, F and F+ with dimensions of 100 mm X 100 mm X 20 mm. These ceramic tiles were assessed using a simplified ceramic armour module consisting of the ceramic tile sandwiched between a cover plate and a backing plate. The test samples were made of either single tile module or multiple tile modules. They were tested against tungsten alloy long rod projectiles at a nominal velocity of 1250m/s. Experimental results showed that ballistic performance of the ceramic correlated with hardness but not fracture toughness, based on mass efficiency. Fracture toughness correlated instead with the damage radius in the ceramic. Simulation using LS-DYNA revealed that improved ballistic performance of the ceramic tiles was due to long dwell time. High fracture toughness of ceramics could suppress damage by tensile stress wave generated. [ABSTRACT FROM AUTHOR]

This ballistics study examines whether saline breast implants can decrease tissue penetration in firearm injuries. We hypothesize that the fluid column within a saline breast implant can alter bullet velocity and/or bullet pattern of mushrooming. The two experimental groups included saline implants with 7.4 cm projection and a no implant group. The experimental design allowed the bullet to pass-through an implant and into ballistics gel (n = 10) or into ballistics gel without passage through an implant (n = 11). Shots that passed through an implant had 20.6% decreased penetration distance when compared to shots that did not pass-through an implant; this difference was statistically significant (31.9 cm vs. 40.2 cm, p < 0.001). Implant group bullets mushroomed prior to gel entry, but the no implant group mushroomed within the gel. Bullet passage through a saline breast implant results in direct bullet velocity reduction and earlier bullet mushrooming; this causes significantly decreased ballistics gel penetration. [ABSTRACT FROM AUTHOR]

A review of the literature concerning the fate and behavior of gunshot residue ( GSR) is presented. A number of concomitant parameters including firearm and ammunition type, plume and GSR material characteristics, travel distances, chemical composition and GSR morphology are critically discussed in relation to their effects on the distribution and deposition, transfer and persistence processes of GSR. The underlying mechanisms associated with such processes are also considered. Knowledge of these processes on GSR materials could provide valuable information concerning scene preservation and subsequent forensic sampling. The number of GSR particles deposited can vary significantly with each firearm discharge, highlighting the potential to produce distinctive data in each individual case. With the continual development and compositional changes of new ammunition types, further evaluation of the effect these processes may have on GSR evidence and their possible influence on the interpretation of the analytical results should be given due consideration. [ABSTRACT FROM AUTHOR]

ABSTRACT What is violence? This article explores conceptions of violence from the perspective of scientists engaged in weapons research. Ballistics scientists are routinely excluded from the 'violent' label on grounds of class, status, education, and emotional comportment. The article analyzes the science of ballistics through the lenses of ethics and emotions. How do scientists justify experiments in ballistics, or the science of designing weapons and other technologies aimed at destroying environments and inflicting wounds (often fatal) and other forms of injury on people and nonhuman animals? In stark contrast to those who analyze weapons development as an objective science and who impart violent agency to autonomous technologies, I situate wound ballistics as a branch of applied moral philosophy. Its practice always involves an 'ought.' Although the central job of ballistics scientists is the 'effective production of wounds,' this is not regarded as violent, except by their victims, of course. In part, this lacuna is due to an ideological relationship forged between 'violence' and particular emotional states. It is also part of a political project defining 'the human.' [ABSTRACT FROM AUTHOR]

Damage produced by high-speed projectiles on organic tissue will depend on the physical properties of the tissues. Conditioning organic tissue samples to human core body temperature (37°C) prior to conducting ballistic experiments enables their behavior to closely mimic that of living tissues. To minimize autolytic changes after death, the tissues are refrigerated soon after their removal from the body and re-heated to 37°C prior to testing. This research investigates whether heating 50-mm-cube samples of porcine liver, kidney, and heart to 37°C for varying durations (maximum 7 h) can affect the penetration response of a high-speed, steel sphere projectile. Longer conditioning times for heart and liver resulted in a slight loss of velocity/energy of the projectile, but the reverse effect occurred for the kidney. Possible reasons for these trends include autolytic changes causing softening (heart and liver) and dehydration causing an increase in density (kidney). [ABSTRACT FROM AUTHOR]

Ballistic imaging systems can help solve crimes by comparing images of cartridge cases, which are recovered from a crime scene or test-fired from a gun, to a database of images obtained from past crime scenes. Many U.S. municipalities lack the resources to process all of their cartridge cases. Using data from Stockton, CA, we analyze two problems: how to allocate limited capacity to maximize the number of cartridge cases that generate at least one hit, and how to prioritize the cartridge cases that are processed to maximize the usefulness (i.e., obtained before the corresponding criminal case is closed) of hits. The number of hits can be significantly increased by prioritizing crime scene evidence over test-fires, and by ranking calibers by their hit probability and processing only the higher ranking calibers. We also estimate that last-come first-served increases the proportion of hits that are useful by only 0.05 relative to first-come first-served. [ABSTRACT FROM AUTHOR]

Research on armor ceramics created only limited success in its search for relations between mechanical properties and the ballistic efficiency of this class of materials. Also TNO performed research on this subject using a range of experimental test set-ups (mainly using small and mid-caliber rounds) and diagnostic tools on a range of ceramic materials and various tile thicknesses. This research has highlighted the large role that inertia (mass) plays during the projectile-target interaction process, which proved to be more dominant than the mechanical ceramic material properties. In fact, all our experimental results on the performance of ceramic armors, can be well understood from an inertia point of view. This includes the widely accepted (increasing) order in ballistic efficiency of the most used armor ceramics when tested at equal areal density: Alumina, SiC, B4C. Based on the gained knowledge, TNO has developed an engineering model for ceramic based armor (ceramic strike face with/without a backing material) that can quantify the projectile-target interaction and quite accurately calculates the mass-loss and deceleration of the projectile in a timeresolved manner. Understanding the large role of inertia could change the direction of the development of advanced armor ceramics. [ABSTRACT FROM AUTHOR]

Projectile components that are traditionally radiolucent can be of considerable importance in determination of weapon type and caliber, but they are often missed on evaluation of postmortem radiographs. We hypothesized that these components would be significantly better visualized by evaluation of computed tomography (CT) scans compared to the practice standard of radiography alone. In this project, potentially radiolucent projectile components were both pulled apart and fired, and the radiolucent components were recovered. These components were embedded in blocks of ballistics gelatin and were imaged using both radiography and CT. The scans were evaluated by three blinded, board‐certified radiologists for the presence/absence of projectile components and true‐negative regions in each block. If a radiologist indicated visualization of a projectile component, they were further requested to describe their observation. It was found that traditionally radiolucent projectile components are not significantly more often identified on CT scans than radiography (p < 0.05). [ABSTRACT FROM AUTHOR]

With the aim of providing better control of shooting experiments performed with replicas of prehistoric projectiles, we have conducted an instrumental archaeology study on the efficiency of prehistoric projectile points by placing emphasis on their adhesion and ballistic characteristics. In order to avoid any reproducibility problems, hafting adhesives were made with controlled mixtures of commercial rosin (also called 'colophany') and beeswax added as a plasticizer. An original experimental device has been developed to instrument a bow, allowing the control of both the trajectories and the velocities of the different shoots. In the course of an experimental programme on Sauveterrian microliths from the Mesolithic period of the South of France, the experimental system was applied to composite replica projectile tips of Mesolithic hunters. Arrows being shot at transparent targets were filmed in order to evaluate the penetration length and residual damage. Interestingly, this study reveals that the properties of the mixture are highly dependent on the velocity of the arrows. It was shown that-contrary to previous experiments that usually used a mixture in which rosin predominates- the most efficient adhesive is made of 70 wt% beeswax with only 30 wt% rosin. This result is of great importance for improving further shooting experiments and overcoming the problems frequently mentioned due to the loss of the flint armatures before they reach the animal target, or at least before penetration. When using this appropriate mixture, the lateral armatures are resistant to most of the shots. Experiments performed on real boars' flesh have also shown that the presence of lateral microliths allows the laceration inflicted on the target to be enlarged. Finally, a critical parameter has been identified, which is the location on the arrow of the microlithic element. [ABSTRACT FROM AUTHOR]

The micro‐motion feature extraction of precession target is an effective way for discriminating warhead from decoy in missile ballistic defence. Generally, traditional methods based on high‐resolution range profile (HRRP) sequences put forward high requirements on modulation bandwidth for the system, increasing the complexity of the system significantly. Utilising single‐frequency ladar without modulation, the authors proposed a precession parameter extraction algorithm of precession target based on high‐resolution Doppler profile (HRDP) sequences. Firstly, they model the Doppler bandwidth of the cone‐shaped precession target with the observation angle. Under the assuming that the measurement error obeys zero‐mean Gaussian distribution, the probability density function of Doppler bandwidth is established. Then, the precession parameters are estimated with measured Doppler profile sequences through maximum likelihood estimation method. Compared with the methods based on HRRPs, the proposed method based on the Doppler profile has lower requirements on the system and easier to implement. Laboratorial data has been used to validate the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

Micro‐Doppler (mD) characteristics of the ballistic targets have attracted great attention due to the potential in target discrimination. However, current investigations mainly focus on blunt‐nosed cone and cone‐cylinder‐shaped targets. In practical applications, ballistic targets are always designed as the streamlined shape due to smaller aerodynamic resistance and lower detectability. In this Letter, the mD characteristics of streamlined ballistic targets are analysed. Owing to the unique mD signatures, the sliding scattering centre induced by the reflection from the streamlined curved surface is particularly focused. Finally, simulation results via the electromagnetic computation verify the correctness of the analysis. [ABSTRACT FROM AUTHOR]

Automated firearms identification ( AFI) systems contribute to shedding light on criminal events by comparison between different pieces of evidence on cartridge cases and bullets and by matching similar ones that were fired from the same firearm. Ballistic evidence can be rapidly analyzed and classified by means of an automatic image analysis and identification system. In addition, it can be used to narrow the range of possible matching evidence. In this study conducted on the cartridges ejected from the examined pistol, three imaging areas, namely the firing pin impression, capsule traces, and the intersection of these traces, were compared automatically using the image analysis and identification system through the correlation ranking method to determine the numeric values that indicate the significance of the similarities. These numerical features that signify the similarities and differences between pistol makes and models can be used in groupings to make a distinction between makes and models of pistols. [ABSTRACT FROM AUTHOR]

For a ceramic armour impacted by a long rod projectile, increasing the dwell-to-penetration transition velocity significantly improves its ballistic performance, whereas it can be achieved by prestressing of the ceramic or placing a buffer over the impact surface. In this paper, numerical simulation using the AUTODYN hydrocode is conducted to investigate how dwell-to-penetration transition is affected by the radial prestress and the presence of a buffer. Taking account of the pressure-dependent strength of SiC ceramics, it is found that distribution of hydrostatic pressure and equivalent stress in the ceramics controls damage initiation and dwell-to-penetration transition. Ceramic damage initiates from the edge of the projectile and then forms a damaged zone in front of the projectile. Compared to the radial prestress, the buffer more effectively suppresses damage initiation to fulfil interface dwell at a higher transition velocity. [ABSTRACT FROM AUTHOR]

Making intertemporal choices (choosing between rewards available at different points in time) requires determining and comparing the subjective values of available rewards. Several studies have found converging evidence identifying the neural systems that encode subjective value in intertemporal choice. However, the neural mechanisms responsible for the process that produces intertemporal decisions on the basis of subjective values have not been investigated. Using model-based and connectivity analyses of functional magnetic resonance imaging data, we investigated the neural mechanisms underlying the value-accumulation process by which subjective value guides intertemporal decisions. Our results show that the dorsomedial frontal cortex, bilateral posterior parietal cortex, and bilateral lateral prefrontal cortex are all involved in the accumulation of subjective value for the purpose of action selection. Our findings establish a mechanistic framework for understanding frontoparietal contributions to intertemporal choice and suggest that value-accumulation processes in the frontoparietal cortex may be a general mechanism for value-based choice. [ABSTRACT FROM AUTHOR]

The field of forensic injury biomechanics is an emerging field. Biomechanically validated tools may assist interdisciplinary teams of investigators in assessing mechanisms of blunt head trauma resulting in skull fractures. The objective of this study is to assess the biofidelity of spherical, frangible skull-brain ( SB) surrogates. Blunt impacts were conducted at 20 m/s, using an instrumented 103 g rigid impactor, to the temporo-parietal region of four defleshed cephalic postmortem human subjects ( PMHS). Force-deformation response, fracture tolerance, and fracture patterns were recorded for comparison to spherical skull-brain surrogates. Three brain substitutes were assessed: 10% gelatin, lead shot with Styrofoam and water. Force-deformation response of the skull-brain surrogates was similar to defleshed PMHS up to the point of fracture; however, none of the surrogates fractured at tolerance levels comparable to the PMHS. Fracture patterns of the skull-brain surrogates were linear and radiating, while PMHS fractures were all depressed, comminuted. [ABSTRACT FROM AUTHOR]

A series of ballistic impact experiments were conducted against a borosilicate glass (Borofloat®33) bonded to a polycarbonate substrate. Two of the objectives of the experiments were to measure crack velocities in the glass, and to measure the damage velocity in the glass. The speed of distinct propagating cracks was found to be 1.92 ± 0.03 km/s, independent of impact velocity. The maximum rate of damage propagation was found to be a function of impact velocity, but the damage velocity plateaued at 2.07 ± 0.04 km/s. [ABSTRACT FROM AUTHOR]

The burning of compacted modified propellant charges applied as a traveling charge in the hybrid shot scheme was studied. The block charges were manufactured by pressing fine propellant grains coated by a thin film of polyvinyl butyral. A stick from several pressed pellets was insulated over its lateral surface by a thin layer of silicon paste, glued to the back of the projectile and inserted into the barrel of the 23-mm smooth-bore laboratory gun. The loose-packed accelerator charge was placed in the breech. Combustion was initiated by an igniter plug placed between the traveling and breech charges. A set of piezoquartz gauges placed in the breech and along the barrel, as well as a frame-target device were used for recording characteristics of the firings. It is shown that blocks of this type, applied as the traveling charge, provide a stable burning process resulting in high ballistic performance. The block traveling charge preserves its integrity in the course of its motion along the barrel, and burning envelopes its total mass when pressure in the breach passes the maximum value. The descending portion of the pressure diagram demonstrates appreciable transformation, with convex or secondary hump sections. The shape of spatial pressure profiles behind the moving projectile is also transformed, and the pressure at the projectile butt end may be higher than the pressure in the breech. Compared to the conventional charges at the same maximum pressures the muzzle velocity increment attains 340 ms-1 (or 23%) for a light 35-g projectile and 200 ms-1 (or 19%) for a heavy 104-g projectile. [ABSTRACT FROM AUTHOR]

ABSTRACT The purpose of this review is to introduce the interested reader to the literature on the use of silica glasses in ballistic applications. These applications include optically transparent windows (where their amorphous nature, appropriate band gap, and cheapness make them ideal window materials) as well as layers in opaque armours designed to be resistant to shaped charges. In the latter application, their increase in volume (bulking) on fracture disrupts the shaped charge jet. Other topics covered in this review include low-velocity damage by windborne debris, liquid and solid impact, dynamic methods of testing (Hopkinson pressure bar, Taylor impact, and plate impact shock loading), and constitutive models. The use of glass as a shaped charge is also discussed. [ABSTRACT FROM AUTHOR]