流弹现象的判断

流弹是一个较为常见的枪击现象,它是指普通动能枪械击发后,击中了瞄准线(或弹道危险界)以外物体的弹头。这种某人或物体被流弹击中的现象可以称为流弹现象。流弹状态的弹丸,同样具备一定的动能,有一定的杀伤力,对生命和财产可以造成一定的危害;同时,由于射手不能控制流弹阶段的     

美国枪害与美国文化

美国的枪械管制比瑞士严、比 英国松,但其枪械却成社会一大公害,文章启 示我们,法律以文化为土壤。     

公安民警枪械训练枪口指向安全问题思考

本文通过文献资料法、观察法,对表现形式多样的公安民警枪械训练安全问题中枪口指向问题进行归纳和总结,并找出其存在的原因和训练措施,为公安民警枪械训练提高理论依据。     

民国警察枪械走火后

1932年初秋,国民政府的首都南京市发生了一起“警察枪械走火伤亡事件”,由于其时正处于刚刚发生“中国银行抢劫案”的敏感阶段,该事件深受首都警察厅重视,数日内投注了不少精力,最后总算顺利处置……     

发射弹头痕迹特征的形成变化机理及应用

由于各种枪械的机件特征不同,枪支发射时将在弹头上留下反映枪械机件特点的种类及特定特征。通过研究枪械生产制作和使用过程中其部件特征形成的基础上,从弹道学原理入手,分析了枪支发射过程中弹头痕迹形成的机理和痕迹特征的变化因素,为枪支同一认定鉴定中检材与样本特征产生差异的原因分析及得出可靠的鉴定意见提供了科学的理论依据和实践方法。     

发射弹头痕迹特征的形成变化机理及应用

由于各种枪械的机件特征不同,枪支发射时将在弹头上留下反映枪械机件特点的种类及特定特征.通过研究枪械生产制作和使用过程中其部件特征形成的基础上,从弹道学原理入手,分析了枪支发射过程中弹头痕迹形成的机理和痕迹特征的变化因素,为枪支同一认定鉴定中检材与样本特征产生差异的原因分析及得出可靠的鉴定意见提供了科学的理论依据和实践方法.     

枪杆子"闹革命"

自从19世纪枪的发明以来,枪便与革命结下不解之缘。每每在社会大变革之际,对立双方总是试图首先掌握好枪杆子,枪杆子掌握在谁的手里也往往成为决定谁赢谁输的关键因素之一。然而,一成不变的枪械在等待新千年的来临时也等来了一场针对自身的革命。2000年4月,澳大利金属风暴公司与布里斯班弹道技术公司研制出世界上第一支完全电子化的手枪,使手枪从传统的以机械化为代表的工业时代一举跨越几百年的时光进入以电子化为代表的信息时代。传统的军事和警察部门不久后将再次“鸟枪换炮”。     

警察枪械使用权的相关问题浅析

在我国近些年,警察在使用枪械过程中由于使用不当等一系列原因,导致了警察在枪械使用中产生了一些违法行为,甚至犯罪行为,究其原因却是复杂的,这里笔者主要想对这些问题和现象产生的相关问题进行研究和分析。     

撞击角度和速度已知条件下的球形弹丸飞行弹道轨迹算法

针对刑侦工作中弹打玻璃类案件的侦破难点,研究一种用于计算球形弹丸抛射击打玻璃案件中弹丸飞行轨迹的算法。本文以弹丸撞击角度和撞击速度为基础参数,在阐明前置基础数据的前提下,将弹打玻璃类案件中的玻璃窗分为垂直于地面及倾斜于地面两类,采用三角函数计算和参数替换的方法,通过对弹丸撞击瞬间的弹道参数设定、弹孔图像在玻璃平面内的二维图像参数设定、相关角度的描述、计算抛物线轨迹与弹道轨迹朝向等一系列步骤,最终,研究出上述两类玻璃窗的弹道轨迹计算方法。研究表明,弹丸弹道飞行轨迹算法可以还原弹丸飞行的轨迹抛物线,作为现场弹道轨迹重建系统的核心算法使用,为开发弹打玻璃类案件的现场弹道轨迹重建系统提供了关键技术。     

利用自制枪械装置击发制式子弹自杀1例

1案例资料简要案情某男,28岁。2003年12月19日上午9时许,被发现死于路边一夏利出租汽车里。据死者父母介绍,死者平日喜爱枪械,阅读、收集有关枪械的书籍与杂志,近1月内有厌世自杀倾向。在死者家中搜见与现场同规格尺寸的无缝钢管3根、死者的驾驶证件及有关枪械知识的书籍和杂志。现场勘查夏利出租车平稳停放于路边,四门紧闭,除驾驶室门未上锁外,其余门均自内部锁住。车处于熄火状态,手刹止于刹车位。副驾驶位门玻璃破碎,散落于车内的玻璃碎片分布于副驾驶座位上及踏脚处,车外的玻璃碎片分布于2.5m×1.5m范围,集中部位距车门0.4m。副驾驶位上…     

Ballistic fingerprinting databases

This article discusses a number of questions regarding the setting up of ballistic fingerprinting databases, consisting of ammunition components fired by all the firearms held in legal possession. These questions can be classified into three categories--the efficiency of the database, forensic issues, and practical issues to be dealt with. The current New York State legislation is used as an illustration of the choices to be made when setting up a ballistic fingerprinting database. Three important arguments are formulated against the installation of a ballistic fingerprinting database.     

Investigation of the variability in the tool marks produced by modified blank firing pistols on fired 7.65 mm projectiles

Firearms identification has an important place in forensic ballistic investigations since the weapons are widely used in criminal offences. Firearm examiners resolve many case files, through the use of automatic systems or comparison microscopes. Advanced forensic technologies like BALİSTİKA helps to record and analyze non standard ballistic evidence. In today's world, with the ease of access to materials and production technique information, pistols modified from blank firers are frequently encountered as crime tools. In this study, the characteristics of 7.65 mm fired cartridge cases obtained by controlled shots from blank firing modified pistols were examined, and their detection performances were compared by means of the Balistika system. Although distinctive differences are not expected after successive test shootings, balistically important changes were seen after the use of blank firing modified pistols and the 3D imaging system proved to be useful in observing such differences. The analyses showed that the modifications in weapons lead to variation in the ballistic characteristics and reduce the accuracy of the detection performance, which may result in flawed forensic decisions. It was also found that the deviations in ballistic impressions of modified blank firing pistols were greater than that of standard fabricated and hand-made pistols. This unique study contributed to the forensic sciences literature by focusing on the impact of modified weapons on ballistic characteristics.     

Fabrication of compound nonwoven materials for soft body armor

The primary objective of body armor research is the development of low-cost, lightweight, wearable garments that effectively resist ballistic impact. This study introduces a material intended to reduce nonpenetration trauma by absorbing energy from ballistic impacts. Layers of web were made by low-melting point polyester (LMPET) on unaligned fibers of high-strength polyamide 6 (HSPA6). A compound nonwoven fabric was made by laying high-strength Vectran filaments between two layers of HSPA6-LMPET web. The new fabric underwent needle punching and thermal bonding to form a composite sandwich structure. The new fabric was subjected to a falling weight impact test and a ballistic impact test. The results indicated that the material with the new design reduced maximum indentation depth by 8%. Furthermore, soft body armor made from the material with the new design would cost less to produce and would weigh 22.5% less than conventional soft body armor.     

Injuries of the Head from Backface Deformation of Ballistic Protective Helmets Under Ballistic Impact

Modern ballistic helmets defeat penetrating bullets by energy transfer from the projectile to the helmet, producing helmet deformation. This deformation may cause severe injuries without completely perforating the helmet, termed “behind armor blunt trauma” (BABT). As helmets become lighter, the likelihood of larger helmet backface deformation under ballistic impact increases. To characterize the potential for BABT, seven postmortem human head/neck specimens wearing a ballistic protective helmet were exposed to nonperforating impact, using a 9 mm, full metal jacket, 124 grain bullet with velocities of 400–460 m/s. An increasing trend of injury severity was observed, ranging from simple linear fractures to combinations of linear and depressed fractures. Overall, the ability to identify skull fractures resulting from BABT can be used in forensic investigations. Our results demonstrate a high risk of skull fracture due to BABT and necessitate the prevention of BABT as a design factor in future generations of protective gear.     

A Preliminary Study on Vacuum Metal Deposition as a Standalone Method for Enhancement of Fingermarks on Ballistic Brass Materials

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.     

The effects of certain intermediary target materials and their proximity to ballistic gelatin on jacketed hollow point bullet expansion

Expanding bullets are preferred by law enforcement because of their wounding potential and ability to avoid over-penetration which could result in unintended targets being struck by bullets that perforate their intended targets. Expansion failure for jacketed hollow point (JHP) bullets is commonly attributed to several causes including damage to the bullet's cavity, velocity loss, bullet destabilization and materials from intermediate targets filling the bullet's cavity which can cause expansion failure when the bullet subsequently impacts a soft, fluid-based target such as human tissue or ballistic gelatin. In this study, JHP bullets were fired into ballistic gelatin after passing through selected intermediate targets representing items common to shooting incidents. Velocity loss and bullet destabilization were not factors that contributed to the JHP bullets that experienced expansion failure; however, materials obstructing the bullets' cavities and damage to the bullets' cavities were considered causes for some of the JHP bullet expansion failures. It was determined through this research that most of the target materials caused JHP bullet expansion failure when shored against the ballistic gelatin, but when placed at distances of 7 ft. from the ballistic gelatin, bullets fired through the same target materials did expand. This original and unique study produced findings that are of significant value to shooting incident reconstruction experts and other forensic professionals as shooting incidents can call into question a victim's proximity to a wall or door when a bullet(s) perforated such a target material.     

Maximum flight velocity of blood drops in analysing blood traces

When analysing blood spatters, traces often occur which regarding the collision angle, cannot be allocated to any supposed centre of origin. Drops following highly curved (ballistic) trajectories usually form these types of traces. The reconstruction of such trajectories requires knowledge of the mass, the diameter (of which approximations are known) and the velocity of the blood drops. This article provides an upper range of the velocity in relation to the diameter of the blood drops based on physical laws. This is very helpful in analysing ballistic trajectories.     

Potential Use in Forensics of a Novel Hybrid Gelatin—Dynamic Impact Assessment

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.     

Does a sixth mechanism exist to explain lightning injuries?: investigating a possible new injury mechanism to determine the cause of injuries related to close lightning flashes

Five mechanisms have been described in the literature regarding lightning injury mechanisms. A sixth mechanism is proposed in this article, namely, lightning barotrauma. A simple laboratory experiment was conducted using ordnance gelatin for ballistic studies. Lightning was simulated in a high-voltage laboratory using an 8/20-microsecond current impulse generator and discharged through ballistic gel. Temporary and permanent cavity formations were confirmed. The cavities formed were directly proportional to the currents used. Findings suggest that a sixth mechanism of lightning injury, namely, barotrauma, should be considered.