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Reedy said they unearthed coins, lipstick cases, toys, tools from past logging activities and plenty of bullets from 20th-century hunters. Brian Reedy has been plagued by one question: Where, precisely, did the first shots of the French and Indian War take place?. [Extracted from the article]

Since the toxic effect of lead on birds has led to a ban on this heavy metal for hunting in wetlands, numerous alternative materials exist on the European market, such as copper, iron, bismuth and tungsten. However, these materials are neither tested for their impact on the environment nor for their killing effect. Due to the complex effect of shot on game, there are no exact guidelines for testing the killing effect. There are only some recommendations on how to assess the performance of conventional lead shot cartridges. These standards do not consider different physical and mechanical properties (density, deformation behavior, hardness, brittleness) of new alternative shot materials and should be updated likewise. For this reason, the Wannseer Norm (LAMPEL and SEITZ, 1983), which is an admitted guideline for conventional lead shot in Germany, was modified by observations of the kinetic energy as an indicator of the ballistic coefficient for a comparative investigation of conventional and alternative shotshells. In addition to the coverage of a 16-field grid we analyzed ballistic criteria based on hits and kinetic energy of the shot pellets on specific surface areas as well as the radial spread of the shot pattern. The coverage is calculated from the number of segments which must contain a minimum of hits or a minimum kinetic energy. Generalized linear models were used to compare different shot types with the same caliber and shot diameter based on these criteria. It was noticeable that shotshells differed in terms of the shots' kinetic energy, as compared to their number of hits. For this reason, it has to be discussed to what extent the energy aspect should be taken into account in new standards (for alternative materials in particular). With regard to the criteria examined in this study, the shotgun cartridges Rottweil Steel Game and Rottweil Ultimate achieved at least the same target ballistic performance as conventional lead shotshells. Furthermore, an alternative shotshell called FOB Sweet Copper was repeatedly conspicuous in the study and seems to be unsuitable for hunting. This demonstrates the urgent need to introduce standardized criteria for testing the environmental impact and the killing effect of game shot in Germany and the EU. For the latter, our study should provide an initial approach. [ABSTRACT FROM AUTHOR]

The article features Wang Zeshan, an explosives expert and member of the Chinese Academy of Engineering. It discusses his motivation for majoring in explosives at the Harbin Institute of Military Engineering. It also describes his achievements in conducting research on explosives, including the development of a new charging technology and ballistic theory following the application of a propelling charging technology that he invented.

The dynamic characteristics related to micro-motions, such as mechanical vibration or rotation, play an essential role in classifying and recognizing ballistic targets in the midcourse, and recent researches explore ways of extracting the micro-motion features from radar signals of ballistic targets. In this paper, we focus on how to investigate the micro-motion dynamic characteristics of the ballistic targets from the signals based on infrared (IR) detection, which is mainly achieved by analyzing the periodic fluctuation characteristics of the target IR irradiance intensity signatures. Simulation experiments demonstrate that the periodic characteristics of IR signatures can be used to distinguish different micromotion types and estimate related parameters. Consequently, this is possible to determine the micro-motion dynamics of ballistic targets based on IR detection. [ABSTRACT FROM AUTHOR]

The article focuses on the mobile protected firepower offered by Main Battle Tanks (MBTs) against offensive and defensive military targets. Topics discussed include the development of MBTs, the increase of lethality and firepower through digital ballistic computing, and the upgrade of MBTs for combat effectiveness.

Binary discrete nonlinear Schrödinger equation is used to describe dynamics of two-species Bose–Einstein condensate loaded into an optical lattice. Linear inter-species coupling leads to Rabi transitions between the species. In the regime of strong nonlinearity, a wavepacket corresponding to condensate separates into localized and ballistic fractions. Localized fraction is predominantly formed by immiscible solitons consisted of only one species. Immiscible solitons are formed from initially non-separated states after transient chaotic regime. We calculate the finite-time Lyapunov exponent as a rate of wavepacket divergence in the Hilbert space. Appearance of immiscible solitons to spontaneous self-stabilization of the wavepacket. It is found that onset of chaos is accompanied by fast variations of interaction energy and energy of inter-site tunneling. Crossover to self-stabilization is accompanied by reduction of condensate density due to emittance of ballistically propagating waves. [ABSTRACT FROM AUTHOR]

ABSTRACT In wildlife shooting programs, the energy profile of the projectile or bullet (i.e., kinetic energy transferred to the animal), as distinct from caliber (projectile diameter), is an important factor for animal welfare. We examined the role of projectile energy in determining animal welfare outcomes for a typical European rabbit ( Oryctolagus cuniculus) sharpshooting program. We compared 2 projectiles of different energy profiles: low-energy 40-grain .22 long rifle rimfire (.22LR; 198 J) bullets and high-energy 40-grain .222 Remington® centerfire (.222R; 1,433 J) bullets, fired under similar conditions on 3 nights in September 2014, on a livestock grazing property near Broken Hill, New South Wales, southeastern Australia. We used a thermal-imaging camera to collect antemortem data from 500 rabbits that were shot at varying distance. We collected postmortem data via visual inspection from 482 rabbits that were killed. We used these data to compare 3 animal welfare parameters: wounding rate, duration of suffering, and ballistic injuries. We then used regression modeling to measure the effect of projectile type on these welfare parameters while accounting for shooting distance. All animal welfare parameters indicated that .222R projectiles were more humane than .22LR projectiles. When controlling for distance, for rabbits shot with a .22LR compared with a .222R, the odds of nonlethal wounding increased by a factor of 8 and noninstantaneous death increased by a factor of 9. All animal welfare parameters declined with increasing distance for both projectiles. Our results show that projectile energy and shooting distance were critical determinants of animal welfare outcomes in wildlife shooting programs. © 2016 The Wildlife Society. [ABSTRACT FROM AUTHOR]

The article discusses the science behind modern cartridge design including the .300 WSM, 6.5mm Creedmoor, 6mm Creedmoor, and the .224 Valkyrie. The author talks about its design and features and the design characteristics of long-standing traditional cartridges. Topics include impact of design on the projectile performance, bullet aerodynamics, and accuracy standards of design.

A stationary distribution function that describes the entire process of the propagation of relativistic particles, including the transition between the ballistic and diffusion regimes, is obtained. The spacial component of the constructed function satisfies the first two moments of the Boltzmann equation. The angular part of the distribution provides accurate values for the angular moments derived from the Boltzmann equation, and gives a correct expression in the limit of the small-angle approximation. Using the derived function, we study the gamma-ray images produced through the pp interaction of relativistic particles with gas clouds in the proximity of the accelerator. In general, the morphology and the energy spectra of gamma rays significantly deviate from the "standard" results corresponding to the propagation of relativistic particles strictly in the diffusion regime. [ABSTRACT FROM AUTHOR]

The linear ballistic accumulator model is a theory of decision-making that has been used to analyse data from human and animal experiments. It represents decisions as a race between independent evidence accumulators, and has proven successful in a form assuming a normal distribution for accumulation (“drift”) rates. However, this assumption has some limitations, including the corollary that some decision times are negative or undefined. We show that various drift rate distributions with strictly positive support can be substituted for the normal distribution without loss of analytic tractability, provided the candidate distribution has a closed-form expression for its mean when truncated to a closed interval. We illustrate the approach by developing three new linear ballistic accumulation variants, in which the normal distribution for drift rates is replaced by either the lognormal, Fréchet, or gamma distribution. We compare some properties of these new variants to the original normal-rate model. [ABSTRACT FROM AUTHOR]

One of the most intricate problems in terminal ballistics is the physics underlying penetration and perforation. Several penetration modes are well identified, such as petalling, plugging, spall failure and fragmentation ( Sedgwick, 1968 ). In most cases, the final target failure will combine those modes. Some of the failure modes can be due to brittle material behavior, but penetration of ductile targets by blunt projectiles, involving plugging in particular, is caused by excessive localized plasticity, with emphasis on adiabatic shear banding (ASB). Among the theories regarding the onset of ASB, new evidence was recently brought by Rittel et al. (2006) , according to whom shear bands initiate as a result of dynamic recrystallization (DRX), a local softening mechanism driven by the stored energy of cold work. As such, ASB formation results from microstructural transformations, rather than from thermal softening. In our previous work ( Dolinski et al., 2010 ), a failure criterion based on plastic strain energy density was presented and applied to model four different classical examples of dynamic failure involving ASB formation. According to this criterion, a material point starts to fail when the total plastic strain energy density reaches a critical value. Thereafter, the strength of the element decreases gradually to zero to mimic the actual material mechanical behavior. The goal of this paper is to present a new combined experimental–numerical study of ballistic penetration and perforation, using the above-mentioned failure criterion. Careful experiments are carried out using a single combination of AISI 4340 FSP projectiles and 25[mm] thick RHA steel plates, while the impact velocity, and hence the imparted damage, are systematically varied. We show that our failure model, which includes only one adjustable parameter in this present work, can faithfully reproduce each of the experiments without any further adjustment. Moreover, it is shown that the most common failure criterion based on a critical strain is simply inadequate to reproduce the results, due to the linear nature of the damage evolution. The advantages of the energy-based failure criterion are discussed in detail. [ABSTRACT FROM AUTHOR]

The remarkable properties of graphene, including unusually high mechanical strength and stiffness, have been well-documented. In this paper, we combine an analytical solution for ballistic impact into a thin isotropic membrane, with ab initio density functional theory calculations for graphene under uniaxial tension, to predict the penetration resistance of multi-layer graphene membranes. The calculations show that continuous graphene membranes could enable ballistic barriers of extraordinary performance, enabling resistance to penetration at masses up to 100× lighter than existing state-of-the-art barrier materials. The very high elastic wave speed and strain energy to failure are the major drivers of this increase in performance. However, the in-plane mechanical isotropy of graphene, as compared to conventional orthotropic woven textiles, also contributes significantly to the efficiency of graphene as a barrier material. This result suggests that, for barrier applications, isotropic membranes composed of covalently bonded two-dimensional molecular networks could provide distinct advantages over fiber-based textiles derived from linear polymers. [ABSTRACT FROM AUTHOR]

Brownian motion is ballistic on short time scales and diffusive on long time scales. Our theoretical investigations indicate that one can observe the exact opposite--an "anomalous diffusion process" where initially diffusive motion becomes ballistic on longer time scales--in an ultracold atomic system with a size comparable to macromolecules. This system is the center-of-mass motion of a quantum matter-wave bright soliton for which the dominant source of decoherence is three-particle losses. Our simulations show that such unusual center-of-mass dynamics should be observable on experimentally accessible time scales. [ABSTRACT FROM AUTHOR]

In the middle, the bullet is at its maximum height, where wind speeds tend to be greater, so you may need to account for a faster wind gradient. If the wind is blowing directly toward (12 o'clock) or away from the target (6 o'clock), the answer is zero - the wind will have no effect on the bullet. If you shoot in mils, find the 90-degree crosswind that causes your bullet to drift .6 mils at 600 yards. [Extracted from the article]

As the chart below shows, these rifles shoot flatter and hit harder than pistol-caliber straight-wall cartridges. As long as you keep your shots to a reasonable distance, the .450 Bush- master provides plenty of wallop for really big animals such as elk, but like the other straight-wall .44/.45 rifle cartridges, it produces significant recoil. Rifle cartridges for hunting public land must have a minimum bullet diameter of .357 inch, and a case that measures no less than 1.16 inches and no greater than 1.8 inches. [Extracted from the article]

The article presents the discussion on design and working of Oshkosh Joint Light Tactical Vehicle (JLTV) providing the ballistic protection of a light tank containing mission package configurations without sacrificing mobility or transportability.

The article offers information on the Forensic Spotlight, department in the Federal Bureau of Investigation (FBI) Law Enforcement Bulletin (LEB) that present developments in the forensic sciences. It mentions that the articles in the Spotlight includes fingerprinting, ballistics and toxicology. It offers information on the use of black spray paint, with metallic flakes to improve the visual appeal focused on coating.

Using a Lorentz invariant deformed string/gauge duality model at finite temperature we calculate the thermal fluctuation and the corresponding linear response, verifying the fluctuation-dissipation theorem. The deformed AdS5 is constructed by the insertion of an exponential factor exp(k/r²) in the metric. We also compute the string energy and the mean square displacement in order to investigate the ballistic and diffusive regimes. Furthermore, we have studied the dissipation and the linear response in the zero temperature scenario. [ABSTRACT FROM AUTHOR]

In Stephen Hunter's latest book, Game of Snipers, his iconic character is summoned to save the day once again. When I interviewed Hunter - you can find that Q&A at outdoorlife.com/ GOS - I wasn't surprised to learn that he had purchased an Accuracy International rifle in 6.5 Creedmoor for "research" purposes. His trigger time and expertise with that rifle are reflected in the book. [Extracted from the article]

The article offers information on the modern precision-rifle scope with cutting-edge optics and electronics for redefining modern marksmanship. It mentions information on reticles which provide sufficient reference marks to make shots easier while avoiding excess clutter, and information on ergonomics that exposed target turrets and broader ranges of magnification; and also mentions about new Mil-XT reticle by Nightforce Optics Inc.

The article offers information on the 6.5mm Creedmoor, a centerfire rifle cartridge for shooting.

The article talks about annual training in the U.S. army reserve 479th Engineer Battalion's Extended Combat Training (ECl) in Fort Drum, New York based on ballistic breaching. It include details on weapons used during the training comprising M26 modular accessory shotgun system 12-guage shotgun, M2 machine gun, M240B machine gun, MK 19 40-millimeter grenade launcher, and M16A2 rifle.

The article offers suggestions and techniques for handling handguns and discusses the ballistics required in each instance. Topics discussed include need for pointing and shooting at the target, impact of hitting in the central nervous system to ensure immediate collapse, and views of gun writer Finn Aagaard on need for penetration during shooting.

The article informs that ballistics testing has revealed that enhanced combat helmets with helmet sensors do not provide required ballistics protection.

The U.S. had hoped to start nuclear talks with North Korea [ABSTRACT FROM PUBLISHER]

The article evaluates several ballistics software that can calculate shots including Delta V from Lex Talus Corp., Coldbore from Patagonia Ballistics, and Applied Ballistics from Applied Ballistics LLC.