Kinetic Projectile Research Articles

FORENSIC ASPECTS OF THE STUDY OF BALLISTIC CHARACTERISTICS AND DAMAGING PROPERTIES OF LOW-SPEED KINETIC PROJECTILES

During unauthorized rallies, mass gatherings and riots with their extremist escalation into a confrontation with law enforcement agencies, the opposing side of the conflict, in order to remotely contain law enforcement officers and inflict maximum damage on them, actively uses improvised means and widespread objects (stones, fragments of building structures and materials, individual parts of various equipment, etc.), which can be put into free flight with the help of human muscle power or with the help of special throwing devices (slings, slingshots, etc.). Despite their relatively low muzzle velocity, such kinetic projectiles are capable of causing fairly severe bodily injury due to their mass. Since there are no methodological recommendations for determining the ballistic characteristics of these low-velocity kinetic projectiles in modern expert practice in weapons research, the authors conducted experimental studies to determine the data that can be used to calculate their trajectory parameters, as well as to determine their damaging properties.

Characterization and modeling of partial-thickness cutaneous injury from debris-simulating kinetic projectiles

Partial-thickness cutaneous injuries distributed over exposed body locations, such as the face and extremities, pose a significant risk of infection, function loss, and extensive scarring. These injuries commonly result from impact of kinetic debris from industrial accidents or blast weaponry such as improvised explosive devices. However, the quantitative connections between partial-thickness injuries and debris attributes (kinetic energy, shape, orientation, etc.) remain unknown, with little means to predict damage processes or design protection. Here we quantitatively characterize damage in near-live human skin after impact by debris-simulating kinetic projectiles at differing impact angles and energies. Impact events are monitored using high-speed and quantitative imaging to visualize skin injuries. These findings are utilized to develop a highly predictive, dynamic computational skin-injury model. Results provide quantitative insights revealing how the dermal-epidermal junction controls more severe wound processes. Findings can illuminate expected wound severity and morbidity risks to inform clinical treatment, and assess effectiveness of emerging personal protective equipment.

Dynamic Behavior of Kinetic Projectile Impact on Honeycomb Sandwich Panels and Multi-Layer Plates

In order to study the dynamic response associated with the impact of a kinetic projectile on the internal structure of an artificial satellite, we propose a kinetic projectile configuration with non-metallic material wrapping and multiple damage elements. The artificial satellite is simplified as a honeycomb sandwich panel and multi-layer plates. We carried out a ground damage test and finite element dynamic simulation, and we determined the lateral effect and penetration performance of the projectile. Then, we studied the dynamic behavior of the projectile penetrating the honeycomb sandwich panel using a theoretical model. We found that its ballistic limit velocity was 150 m/s, and the deformation of the opening had little relationship with the projectile velocity. Finally, we studied the dynamic response of the kinetic projectile impacting the multi-layer plates under various launch parameters. We found that the launch velocity required to meet the damage requirements was within 325 ± 25 m/s. Projectiles with a higher initial velocity had a stronger ability to penetrate the plates, but initial velocities higher than 325 m/s led to a reduced damage area. The kinetic projectile could adapt to incident angles less than 5° when damaging the plates. With the increasing incident angle, the penetration ability was reduced, and the damage area increased.

Aspects Related to the Analysis of the Terminal Effect of Non-Lethal Kinetic Projectiles

Aspects Related to the Analysis of the Terminal Effect of Non-Lethal Kinetic Projectiles

Kinetic Projectile Injuries Treated During Civil Protests in Los Angeles: A Case Series.

IntroductionDuring protests following the death of George Floyd, kinetic impact projectiles (KIP) were used by law enforcement as a method of crowd control. We describe the injuries seen at a single Level 1 trauma center in Los Angeles over a two-day period of protests to add to the collective understanding of the public health ramifications of crowd-control weapons used in the setting of protests.Case SeriesWe reviewed the emergency department visits of 14 patients who presented to our facility due to injuries sustained from KIPs over a 48-hour period during civil protests after the death of George Floyd.ConclusionLess lethal weapons can cause significant injuries and may not be appropriate for the purposes of crowd control, especially when used outside of established guidelines.

СТАРТОВІ ПІСТОЛЕТИ Й РЕВОЛЬВЕРИ: ПРАВОВЕ РЕГУЛЮВАННЯ ОБІГУ ТА КРИМІНАЛІСТИЧНЕ ДОСЛІДЖЕННЯ

The article deals with the problematic issues of circulation and expert research of products, which are classified by the manufacturer as alarming and signaling weapons, as well as starting pistols and revolvers. The history of origin, evolution and distribution of these objects of ballistic origin in Ukraine and in the world is reviewed. The experience of expert practice of forensic investigation of these devices in the units of the Expert Service of the Ministry of Internal Affairs of Ukraine is analyzed and its comparison with the experience of expert evaluation of these products by employees of expert institutions of the Ministry of Justice of Ukraine. A detailed study of the design features of the most common samples of firearms made by processing products classified by the manufacturer as alarms and alarms, as well as starting pistols and revolvers. Ways to make changes in their design of inverse and irreversible changes in order to bring into a state suitable for firing kinetic projectiles. The methods used by forensic experts in forensic investigation and testing of objects with firearms not classified by the manufacturer for household, sports and special purpose products are described in detail. Examples of illicit trafficking, distribution and use of these products as firearms during the commission of crimes are given. The normative documents that regulate the order of circulation in Ukraine of products with the characteristics of firearms, which the manufacturer classifies as devices of household, sports and special purpose, are analyzed. The basic requirements for alarming and signaling weapons, as well as starting pistols and revolvers by national standards and methods of ballistic examination are considered. The problematic aspects of the Ukrainian national legislation in the sphere of circulation of firearms objects and their consequences for the state are investigated. On the basis of the analysis of the European experience in regulating the circulation of alarm and signal weapons, ways of improving the national legal acts regulating the circulation of similar products in Ukraine have been proposed.

PECULIARITIES OF THE ORIGIN OF LEAD TRACES IN A BORE OF SMOOTHBORE FIREARM

The article is devoted to review of the problem of studying traces of metallizing in a smoothbore firearm bore when firing various types of kinetic projectiles. The features of the mechanism of formation of lead traces in a bore as well as conditions contributing to lead plating are considered. The main cases of detecting traces of lead on bore surface in the course of corresponding multidisciplinary forensic ballistic and chemistry analysis are considered. The main methods for detecting traces of lead in the bore of the studied sample of weapon are described, as well as signs on the basis of which it is possible to establish the type of projectile that was fired in cases when a bore has not been thoroughly cleaned. In the course of the survey on the study of traces of metallization, it was found that the contact-diffusion method is suitable only for qualitative analysis of lead traces, it can be used to determine only the presence of lead and visualize the degree of concentration of the studied metal in the contact zone based on the intensity of color display of chemical reaction. To establish quantitative indicators of the chemical elements that make up the traces of metallization, this method is unpromising. Particular attention is paid to the study of traces of metallization in a bore of traumatic guns. The possible problematic aspects of this kind of research are indicated. It is obvious that research in this direction requires the introduction into practice of more advanced equipment and new approaches aimed at identifying individualizing signs of the nature of traces origin.

DYNAMIC STRENGHT TESTS OF MATERIALS FROM TUNGSTEN HEAVY ALLOYS DESIGED FOR PENETRATORS OF APFSDS-T PROJECTILES

The paper presents results of strength tests for tungsten heavy alloys (WHA) designated for the rods of APFSDS–T kinetic projectiles. The strength tests of WHA materials were carried out in conditions of heavy dynamical loads i.e. by the firing. The paper gives a theoretical concept for the identification of stresses within the critical cross-sections of the investigated projectile, and a description of a testing stand which was specially prepared and equipped with 30 mm smooth bore ballistic barrel, and description of methodology and test results. It was especially interesting to test the material against various dynamical loads originating both from the forces of gas pressure and the crosswise forces occurring at the projectile’s move in the barrel.

CONCEPT OF A SEGMENTED PENETRATOR MADE OF TUNGSTEN HEAVY ALLOYS WITH VARIABLE STRENGTH PARAMETERS

The paper describes a concept of increasing the penetration capacities of kinetic antitank projectiles, having a penetrator made of a tungsten based sinter, through the application of materials with variable mechanical characteristics for penetrator’s particular segments. The influence of alloy additions on some strength parameters for the tung-sten based sinters were assessed by using the literature data, and in the next step by numerical analyses of steel plate penetration process calculated for selected configurations of structural materials of penetrator segments. The summary describes some possibilities for modification of the structure of tungsten based sinters which may decisively improve the penetrating capacities.

Nanoindenting the Chelyabinsk Meteorite to Learn about Impact Deflection Effects in asteroids

Abstract The Chelyabinsk meteorite is a highly shocked, low porosity, ordinary chondrite, probably similar to S- or Q-type asteroids. Therefore, nanoindentation experiments on this meteorite allow us to obtain key data to understand the physical properties of near-Earth asteroids. Tests at different length scales provide information about the local mechanical properties of the minerals forming this meteorite: reduced Young’s modulus, hardness, elastic recovery, and fracture toughness. Those tests are also useful to understand the potential to deflect threatening asteroids using a kinetic projectile. We found that the differences in mechanical properties between regions of the meteorite, which increase or reduce the efficiency of impacts, are not a result of compositional differences. A low mean particle size, attributed to repetitive shock, can increase hardness, while low porosity promotes a higher momentum multiplication. Momentum multiplication is the ratio between the change in momentum of a target due to an impact, and the momentum of the projectile, and therefore, higher values imply more efficient impacts. In the Chelyabinsk meteorite, the properties of the light-colored lithology materials facilitate obtaining higher momentum multiplication values, compared to the other regions described for this meteorite. Also, we found a low value of fracture toughness in the shock-melt veins of Chelyabinsk, which would promote the ejection of material after an impact and therefore increase the momentum multiplication. These results are relevant to the growing interest in missions to test asteroid deflection, such as the recent collaboration between the European Space Agency and NASA, known as the Asteroid Impact and Deflection Assessment mission.

329 Injury Patterns of Less Lethal Kinetic Impact Projectiles Used by Law Enforcement Officers

329 Injury Patterns of Less Lethal Kinetic Impact Projectiles Used by Law Enforcement Officers

Semi-theoretical analyses of the concrete plate perforated by a rigid projectile

Based on the three-stage perforation model, a semi-theoretical analysis is conducted for the ballistic performances of a rigid kinetic projectile impacting on concrete plates. By introducing the projectile resistance coefficients, dimensionless formulae are proposed for depth of penetration (DOP), perforation limit thickness, ballistic limit velocity, residual velocity and perforation ratio, with the projectile nosed geometries and projectile-target interfacial friction taken into account. Based on the proposed formula for DOP and lots of penetration tests data of normal and high strength concrete targets, a new expression is obtained for target strength parameter. By comparisons between the results of the proposed formulae and existing empirical formulae and large amount of projectile penetration or perforation tests data for monolithic and segmented concrete targets, the validations of the proposed formulae are verified. It is found that the projectile-target interfacial friction can be neglected in the predictions of characteristic ballistic parameters. The dimensionless DOP for low-to-mid speed impacts of non-flat nosed projectiles increases almost linearly with the impact factor by a coefficient of 2/(πS). The anti-perforation ability of the multilayered concrete plates is dependent on both the target plate thickness and the projectile impact velocity. The variation range of the perforation ratio is 1–3.5 for concrete targets.

Cardiac Changes After Simulated Behind Armor Blunt Trauma or Impact of Nonlethal Kinetic Projectile Ammunition

Cardiac-related injuries caused by blunt chest trauma remain a severe problem. The aim of this study was to investigate pathophysiological changes in the heart that might arise after behind armor blunt trauma or impacts of nonlethal projectiles. Sixteen pigs were shot directly at the sternum with "Sponge Round eXact I Mpact" (nonlethal ammunition; diameter 40 mm and weight 28 g) or hard-plastic ammunition (diameter 65 mm and weight 58 g) to simulate behind armor blunt trauma. To evaluate the influence of the shot location, seven additional pigs where exposed to an oblique heart shot. Physiologic parameters, electrocardiography, echocardiogram, the biochemical marker troponin I (TnI), and myocardial injuries were analyzed. Nonlethal kinetic projectiles (101-108 m/s; 143-163 J) did not cause significant pathophysiological changes. Five of 18 pigs shot with 65-mm plastic projectiles (99-133 m/s; 284-513 J) to the front or side of the thorax died directly after the shot. No major physiologic changes could be observed in surviving animals. Animals shot with an oblique heart shot (99-106 m/s; 284-326 J) demonstrated a small, but significant decrease in saturation. Energy levels over 300 J caused increased TnI and myocardial damages in most of the pigs. This study indicates that nonlethal kinetic projectiles "eXact iMpact" does not cause heart-related damage under the examined conditions. On impact, sudden heart arrest may occur independently from the cardiac's electrical cycle. The cardiac enzyme, TnI, can be used as a reliable diagnostic marker to detect heart tissue damages after blunt chest trauma.

Numerical Study on the Equivalent Target for Deep Penetration

The influence of radial and axial boundary effect on penetration effect are calculated, numerical simulation are executed to compute the kinetic projectile against deep hard target by finite element code, the boundary effects were achieved for different velocity range. Result shows that the minimal Dt/Dp (diameter ratio of target to projectile) for impact velocity 600m/s is 17.5, while the minimal Dt/Dp for impact velocity 900m/s is 20. Furthermore, the depth of equivalent target to substitute semi-infinite target is twice of penetration depth limit for impact velocity 300m/s, and 1.6 times respectively, for impact velocity 600m/s, 900m/s.

Multisphere Ceramic Composite Concept and its Numerical Study of the Ballistic Response

Numerical investigations were performed to determine the influence of the spherical convex shape ceramic - alumina composite in reference to the standard double layer panel. All versions of the target were verified in an impact test including influence upon the position of the AP (Armor Piercing) 7,62x51HHS impact. The crucial parameter which was used for this verification was change in time of the PROJECTILE kinetic energy. The problem has been solved with the usage of the modeling and simulation methods as well as finite elements method implemented in LS-DYNA software. Space discretization for each option was built by three dimension elements guarantying satisfying accuracy of the calculations. For material behavior simulation specific models including the influence of the strain rate and temperature changes were considered. Projectile’s core made of HHS and aluminum plate material were described by Johnson-Cook model and ceramic target with Johnson-Holmquist model. In the studied panels the area surrounding back edges was supported by rigid wall. The obtained results show interesting properties of the new structures considering their ballistic resistance. However only certain places were chosen for tests, the protection ability against projectile attack is in general higher than the reference model. What is particularly interesting during the 6.6mm from the sphere center impact the sphere surface trajectory deviation effect is present. A projectile is not stopped here by material strength but the front layer shape. Moreover it can be assumed that this phenomenon will take place on majority of points on the sphere surface. Despite this fact, a ceramic multi sphere layer is less susceptible to overall destruction, depending on the impact point. The results of those numerical simulations can be used for designing of modern armor protection systems against hard kinetic projectiles.

Analytical modelling of high velocity impacts of cylindrical projectiles on carbon/epoxy laminates

In this work an analytical model has been developed in order to predict the residual velocity of a cylindrical steel projectile, after impacting into a woven carbon/epoxy thin laminate. The model is based in an energy balance, in which the kinetic projectile energy is absorbed by the laminate through three different mechanisms: linear momentum transfer, fiber failure and laminate crushing. This last mechanism needs the quantification of the through-thickness compressive strength, which has been evaluated by means of quasi-static punch tests. Finally, high velocity impact tests have been accomplished in a wide range of velocities, to validate the model.

Nanoscopic surface modification by slow ion bombardment

We present systematic scanning tunneling microscopy (STM)/atomic-force microscopic (AFM) investigations on nanoscopic defect production at atomically clean surfaces of SiO 2, Al 2O 3 and highly oriented pyrolytic graphite (HOPG) after bombardment by slow (impact energy≤1.2 keV) singly and multiply charged ions under strict ultra-high vacuum (UHV) conditions. Combined STM and AFM studies show that on HOPG only “electronic” but no visible topographic defects are created by such ion bombardment. On the monocrystalline insulator surfaces, well-defined topographic features of typically nm extensions are produced (“potential sputtering”). For Al 2O 3 and HOPG, a clear dependence of the defect size on the projectile ion charge is demonstrated. These results are discussed in view to possible new nanoscopic surface structuring and modification methods for which the kinetic projectile energy plays a minor role only.

The effect of laminate stacking sequence of CFRP filament wound tubes subjected to projectile impact

The work described herein focuses on the effect a change in the laminate stacking sequence has on the ability to dissipate kinetic projectile energy. Two different T800 carbon fibre filament wound tubes in an epoxy matrix with lay-ups of [−35°/+35°/90° 3/−35°/+35°/90° 3/−35°/+35°] (laminate A) and [90° 6/(−35°/+35°) 3] (laminate B) are investigated. The tubes are subjected to impacts up to and above the ballistic limits. The energy dissipated by material failure and friction is quantified and shown to be similar for the two laminates at the respective ballistic limits. The results indicate that laminate B provides the best energy dissipation performance as a result of a higher ballistic limit than laminate A and a difference in the strain energy due to a different local response of the two laminates.

The resistance of silicon carbide to static and impact local loading

The physical nature of the resistance of SiC crystals to static and local impact loading has been examined. Investigation of the temperature dependence of hardness for SiC crystals allows the determination of the characteristic deformation temperature ( T∗ ≈ 1600 K), the parameter α that characterizes the degree of covalence in interatomic bonds (α ≈ 6) and the temperature range in which a phase transition under pressure during indentation is possible ( T < 800 K). Indentation technique gives possibility to construct stress-strain curves for brittle materials and to determine Hugoniot Elastic Limit. During dynamic penetration of a kinetic projectile into a SiC target the phase transition takes place.

Collisions of with neutral : Charge transfer and fragmentation

Fragmentation of fullerenes by collisions with multiply charged ions has been studied experimentally for collision energies of . For high projectile charges the potential energy of the projectiles is mainly responsible for the processes induced: the fragment spectra are dominated by multiply charged parent ions and small fragment ions such as and . With decreasing projectile charge, fragmentation induced by the kinetic projectile energy becomes increasingly important, leading to a decreasing yield of surviving ions and an increasing number of fragments with n in the range 2-12. Widths and shapes of the fragment peaks in the measured time-of-flight spectra allow us to determine the kinetic energy release for various fragmentation processes and to distinguish between evaporation of neutral molecules from vibrationally excited ions on the one hand, and super-asymmetric fission into two charged fragments, on the other.