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Interior ballistics analysis is required for the development of the gun system. Interior ballistics is a complex phenomenon containing the propellant combustion and gas flow and is completed in tens of milliseconds during gun firing. Thus, some data cannot be directly measured by experiment. Numerical analysis is therefore traditionally used to understand the complex gun firing phenomena. In previous studies, the two-dimensional axisymmetric numerical method for interior ballistics using the Eulerian-Lagrangian approach has been developed. There are some limits in depicting the actual phenomena with two-dimensional models. Therefore, a three-dimensional numerical model has been built in the present study. Unlike the conventional method, the calculation has been conducted by separating the physical phenomena into the combustion part and the flow part for simplicity and efficiency. The internal flow in the gun barrel has been calculated by using the STAR-CCM+ and the source terms produced by the propellant combustion has been computed by utilizing the existing code. The developed numerical model has been compared with the AGARD gun results and the simulation of 40 mm gun firings. The reliability of the developed model has been confirmed because the results of the numerical analysis greatly agree with the simulation results. The basis of the three-dimensional analysis of the interior ballistics has been formed through this study. [ABSTRACT FROM AUTHOR]

Estimation of the firing range is often critical for reconstructing gunshot fatalities, where the main measurable evidence is the gunshot residue (GSR). In the present study intermediate-range gunshot wounds have been analysed by means of a micro-computed tomography (micro-CT) coupled to an image analysis software in order to quantify the powder particles and to determine the firing distance. A total of 50 shootings were performed on skin sections obtained from human legs surgically amputated for medical reasons. For each tested distance (5, 15, 23, 30 and 40 cm), firing was carried out perpendicularly at the samples using a 7.65-mm pistol loaded with jacketed bullets. Uninjured skin sections were used as controls. By increasing the firing distance, micro-CT analysis demonstrated a clear decreasing trend in the mean GSR percentage, particularly for shots fired from more than 15 cm. For distances under 23 cm, the powder particles were concentrated on the epidermis and dermis around the hole, and inside the cavity; while, at greater distances, they were deposited only on the skin surface. Statistical analysis showed a nonlinear relationship between the amount of GSR deposits and the firing range, well explained by a Gaussian-like function. The proposed method allowed a good discrimination for all the tested distances, proving to be an objective, rapid and inexpensive tool for estimating the firing range in intermediate-range gunshot wounds. [ABSTRACT FROM AUTHOR]

Efforts to understand the trajectory of cannonballs are an interesting example of the tensions between practical and theoretical knowledge. Although Galileo's 1638 parabolic trajectory was an important theoretical step forward, field gunnery practice was guided by Tartaglia's 1537 'mixed motion' model until the eighteenth century. In 1742, Benjamin Robins published New principles of gunnery, and revolutionized the study of ballistics by suggesting the projectile's initial velocity—not its range—was the appropriate parameter to consider in accounting for air resistance. In 1745, Leonard Euler produced a German translation of New principles, adding his own extensive commentary. Euler's annotated translation quickly became a standard text—Napoleon Bonaparte studied ballistics from the French version—thereby influencing the education of artillery officers and, eventually, of all engineers. This paper surveys the contributions of Robins and Euler to mathematical ballistics theory, examines the influence of these developments on the education of eighteenth-century military engineers, and considers the extent to which the history of ballistics theory supports the thesis that the drive to reconcile practical knowledge with theoretical knowledge can be a critical element in shaping mathematical theory. We close with comments concerning the use of this history in today's classroom. [ABSTRACT FROM AUTHOR]

The important mechanisms for defeating armor piercing (AP) projectiles are reviewed in this paper. These mechanisms are based on the compressive strength of the target material (its inherent resistance to penetration) and on the asymmetrical forces which it exerts on the threat, through proper geometrical arrangements. We discuss the basic features of the resistance to penetration, starting with the classical analysis of the cavity expansion process in elasto-plastic solids. This property of the target is responsible for the deceleration of hard cored projectiles and for the erosion of long rods, under normal impact conditions. We then discuss the asymmetrical interaction of AP projectiles with inclined plates (metals and polymers) and with ceramic spheres. These asymmetric forces are responsible for their deflection and breakup. Our work combines experimental observations with numerical simulations and engineering models, which enhance the understanding of the various phenomena encountered in these complex situations. This understanding is necessary for optimizing the performance of any armor design against a given threat. [ABSTRACT FROM AUTHOR]

The article offers information about the function of the military academies and universities in the development of artillery in Russia. The country has entrusted the academies to improve the theories for artillery firing method and techniques with the support of the external ballistic. The direction set forth leads to the perfect setting of fire methods, accuracy, and effectiveness of the artillery and gunnery control theory.