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This paper proposes a cost-effective, compact, noncontacting optoelectronic targeting system for measuring the distribution of projectile motion. The major elements of this system include a light emitting diode (LED) array, photodiode detecting array, double-layered aperture arrays, adaptive threshold circuit, and date acquisition. Through cooperating with double-layered aperture arrays, the system effectively reduces the radiation width of the light source to the photodiode detecting surface, and filters out the influence of incident light from the adjacent apertures on both sides above each photodiode to the corresponding photodiode detecting surface. It realizes that the response of the photodiode array corresponds to the coordinates of the light screen one by one. Through the sensitivity analysis of the light screen of the system, the system detecting threshold when the projectile passes through the light screen is calculated, and the corresponding adaptive threshold circuit is designed to prevent misjudgment when the system works. The measuring error of the system can reach &plusmn, 2 mm by experimental verification. Compared with other projectile&rsquo, s distribution measuring systems, the proposed system has the advantages of having high precision, convenient debugging, is nondestructive, and is a noncontact system.

As part of a research program, it was desired to better understand the impact of the rotating chamber alignment with the barrel throat on the precision and accuracy of a novel cased telescoped (CT) ammunition firing rifle. In order to perform the study, a baseline CT ammunition chamber which was concentric with a Mann barrel bore was manufactured. Additionally, six chambers were manufactured with an offset relative to the barrel bore. These chambers were used to simulate a misaligned chamber relative to the bore axis. Precision and accuracy tests were then performed at 200 m in an indoor range under controlled conditions. For this project, 5.56 mm CT ammunition was used. As the chamber axis offset relative to the gun bore was increased, the mean point of impact was displaced away from the target center. The shift in the impact location is explained by the presence of in-bore yaw which results in lateral throw-off and aerodynamic jump components. The linear theory of ballistics is used to establish a relationship between the chamber misalignment and the resulting projectile mean point of impact for a rifle developed to fire CT ammunition. This relationship allows for the prediction of the mean point of impact given a chamber misalignment.

The objective of this study was to investigate the terminal ballistics of police shootings in which the bullets went through any motor vehicle structure before fatally wounding the occupants. 6 cases that occurred in Porto district between 1998 and 2013 were studied. The firearms used were 7.65 mm (n = 1) or 9 mm (n = 3) calibre semi-automatic pistols and 9 mm calibre submachine guns (n = 2); the bullets were full metal jacket type. The metal jacket of the collected projectiles was totally or partially destroyed in 3 cases. It exhibited a deformed structure in all cases. The trajectories of the bullets in the vehicles were always more or less linear, even when initial impact was at an oblique angle. The entry holes in the victims' bodies were larger or much larger in size than the calibre of the bullets. They were located, with the exception of one of the cases, in the left half of the body. The trajectories in the victims' bodies were from front to back, in one case, and from back to front in all others. Exit wounds were only found in two cases. Death occurred immediately after the victim was shot only in one case, despite a vital structure has been hit in all cases. The cases studied support the idea that the use of firearms against vehicles with the sole intention of immobilisation entails uncontrollable danger to the lives of the occupants, and especially when done by police forces not specifically trained for that purpose. Therefore, such use of firearms should be avoided.

Since common energetic materials are not easily compatible with existing additive manufacturing techniques, the Energetic Materials department of TNO in the Netherlands worked closely together with the Additive Manufacturing and Material Solutions groups of TNO to develop new types of energetic material that can be processed in standard 3D printers, aiming at better performance and greater flexibility in the manufacturing of energetic products. This contribution gives an overview of potential applications for additive manufacturing of energetic materials, ranging from rocket propellants to explosives, gun propellants, and other applications. The paper then briefly describes TNO’s research efforts since 2013 into AM of energetic materials. Next, the work performed on additive manufacturing of gun propellants, using stereolithography, is described in more detail, including the results of the material development and characterization, and performance test results, including test firings with a 30 mm gun. The paper concludes with an overview of the current status of the research at TNO, as well as a definition of the next steps to be taken and a vision of the future of additive manufacturing of energetic materials.

A novel miniaturised system for measurement of the in-flight characteristics of an arrow is introduced in this paper. The system allows the user to measure in-flight parameters such as the arrow's speed, kinetic energy and momentum, arrow drag and vibrations of the arrow shaft. The system consists of electronics, namely a three axis accelerometer, shock switch, microcontroller and EEPROM memory embedded in the arrow tip. The system also includes a docking station for download and processing of in-flight ballistic data from the tip to provide the measured values. With this system, a user can evaluate and optimize their archery equipment setup based on measured ballistic values. Recent test results taken at NIST show the accuracy of the launch velocities to be within +/− 0.59%, when compared with NIST's most accurate ballistic chronograph.

Firearm injuries to the head and neck have a potential for fatal complications caused by damage to neurovascular structures in the region. We herewith present a case of a missile injury to the face, caused by a bullet from a rifle with high muzzle energy that slackened while penetrating a vehicle before hitting the victim. The bullet advanced through the retrofacial spaces following a non-linear course and was retained within the opposite parapharyngeal region without injuring any vital structure. The resultant damage was a 'low-velocity injury'. However, it is noteworthy that the missile had still retained enough energy to penetrate the tissue and travel in a 'dissecting' fashion. It is likely that the blunting of the missile during vehicle penetration and the compactness of the anatomical structures bordering the head and neck spaces, such as fascia and tendons, forced the projectile to follow a non-linear inter-structural path. This case yet again demonstrates that the magnitude of firearm-related tissue damage may also depend upon the shape of the projectile and confirms that the head and neck spaces have anatomical integrity rather than just being arbitrarily designated topographical areas. It has also been confirmed that non-surgical approach with regular follow-ups is a viable option for uncomplicated head and neck injuries. (C) 2010 Elsevier Ireland Ltd. All rights reserved.