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The article of record as published may be found at http://dx.doi.org/10.1520/JTE20130136 High-speed video has been used by ballistics engineers as a cost-effective technique to measure the spin-rates of both spin-stabilized and fin-stabilized artillery projectiles. Often at test ranges, state-of-the-art video systems are used to verify critical launch events following muzzle exit. From manual analysis of these videos, important performance metrics such as velocity, pitch angle, and spin-rate can be estimated. To do this, operators step through the video frames and record the time at which certain fiducial markings or numbered stripes are observed on the projectile as it rotates. The different methods evaluated in this paper are automated processes for calculating the muzzle-exit spin-rate from launch videos of spin-stabilized artillery projectiles painted with stripes. Image processing and computer vision techniques are employed to segment the shape of the projectile and extract the stripe pattern in each video frame. The most accurate algorithm estimates are validated to within 0.02 % for both laboratory and computer-simulated flight video and within 0.13 % for manual analysis of real flight video. The sensitivities of the methods to image resolution, video frame-rate, and the length of flight captured are evaluated. Areas of continued research and recommendations for increasing the accuracy of measurements in future tests are also identified.

There have been several anthropological studies on trauma analysis in recent literature, but few studies have focused on the differences between the three mechanisms of trauma (sharp force trauma, blunt force trauma and ballistics trauma). The hypothesis of this study is that blunt force and ballistics fracture patterns in the skull can be differentiated using concentric fractures. Two-hundred and eleven injuries from skulls exhibiting concentric fractures were examined to determine if the mechanism of trauma could be determined by beveling direction. Fractures occurring in buttressed and non-buttressed regions were examined separately. Contingency tables and Pearson's Chi-Square were used to evaluate the relationship between the two variables (the mechanism of trauma and the direction of beveling), while Pearson's r correlation was used to determine the strength of the relationship. Contingency tables and Chi-square tests among the entire sample, the buttressed areas, and the non-buttressed areas led to the null hypothesis (no relationship) to be rejected. Pearson's r correlation indicated that the relationship between the variables studied is greater than chance allocation.

A bullet signature measurement system based on a stylus instrument was developed at the National Institute of Standards and Technology (NIST) for the signature measurements of NIST RM (Reference Material) 8240 standard bullets. The standard bullets are developed as a reference standard for bullet signature measurements and are aimed to support the recently established National Integrated Ballistics Information Network (NIBIN) by the Bureau of Alcohol, Tobacco and Firearms (ATF) and the Federal Bureau of Investigation (FBI). The RM bullets are designed as both a virtual and a physical bullet signature standard. The virtual standard is a set of six digitized bullet signatures originally profiled from six master bullets fired at ATF and FBI using six different guns. By using the virtual signature standard to control the tool path on a numerically controlled diamond turning machine at NIST, 40 RM bullets were produced. In this paper, a comparison parameter and an algorithm using auto-and cross-correlation functions are described for qualifying the bullet signature differences between the RM bullets and the virtual bullet signature standard. When two compared signatures are exactly the same (point by point), their cross-correlation function (CCF) value will be equal to 100%. The measurement system setup, measurement program, and initial measurement results are discussed. Initial measurement results for the 40 standard bullets, each measured at six land impressions, show that the CCF values for the 240 signature measurements are higher than 95%, with most of them even higher than 99%. These results demonstrate the high reproducibility for both the manufacturing process and the measurement system for the NIST RM 8240 standard bullets.

Ballistics imaging technology has received national attention as a potent tool for moving the law enforcement response to violent gun criminals forward by linking multiple crime scenes to one firearm. This study examines the impact of ballistics imaging technology on the productivity of the Boston Police Department's Ballistics Unit. Using negative binomial regression models to analyze times series data on ballistics matches, we find that ballistics imaging technology was associated with a more than sixfold increase in the monthly number of ballistics matches made by the Boston Police Department's Ballistics Unit. Cost-effectiveness estimates and qualitative evidence also suggest that ballistics imaging technology allows law enforcement agencies to make hits that would not have been possible using traditional ballistics methods.

This paper compares the ballistic impact response of advanced fiber composites and metals. These comparisons are made within the framework of a methodology that defines the necessary data and analysis requirements for evaluating the survivability of combat aircraft designs. A side-by-side comparison was made of the available residual strength and damage size test data for metals and fiber composites damaged by small arms projectiles. In addition, the available composite data was used to extend a model for predicting the ultimate strength of composite tension panels damaged by bullets. This model was used in conjunction with an existing model for metals to extend the comparisons to equal strength, equal stiffness, or equal weight structural panels. The results show that both metal and fiber composite panels lose a significant percent of their undamaged strength (50 percent or more) when impacted with small arms projectiles. For the cases considered, the percent reduction in the fiber composite panels was greater than in the metal panels. These results are considered to be preliminary for structural evaluations, however, because only simple panel data were used in the comparison.

The article of record as published may be found at http://dx.doi.org/10.1520/JTE20130107 This paper describes a cost effective automated methodology to analyze launch video of artillery projectiles. Image processing and computer vision techniques are used to segment and classify the projectile shape in each video frame. Within minutes of being fired, the initial position, velocity, and orientation history of the projectile in three-dimensional space is determined at the gun site. An overview of several standard methods used by the Army to characterize pitching and yawing motion of projectiles is included, as well as a discussion of the limitations of these methods. Results from real artillery testing using the automated video analysis method are validated through comparisons to results measured using conventional techniques.

Hunting firearm injuries and fatalities from ricocheted bullets play a minor, but still important, role in forensic medicine and shooting reconstruction. Especially in the area of critical ricochet angles a ballistic analysis is essential to be able to reconstruct hunting accidents. The aim of this study is to analyze ricocheted rifle projectiles (.30-06 Bionic Black and .30-06 Oryx) and shotgun slugs (cal. 12 Brenneke original) from frozen and non-frozen concrete, as well as their ballistic injury potential at a simulated shooting distance of 100 m (rifle projectiles) and 20 m (slugs). Each projectile had a v100 velocity between 370 m/s (shotgun ammunition) and 740 m/s (rifle ammunition) and was shot at an incident angle between 2–20° (rifle ammunition) and 5–35° (shotgun ammunition). To record the angle of ricochet and target energy of each ricocheted projectile, a polycarbonate wall with a reference scale, as well as ballistic soap were used as a final target. At a shooting distance of 100 m, non-ricochet shots are only possible from high seats, but not from deer stands. The critical shooting angle showed a rather high variation for both rifle and shotgun ammunition and was noted between 1.25 times (shotgun ammunition) and 2.5 times (rifle ammunition) higher for frozen concrete compared to non-frozen concrete. All tested ammunition showed remarkable high variations in the ricochet’s angular deviation. Upon the impact of a ricochet, energy levels of over 1000 J were realized with significant injury potential to underlying organs.

The purpose of this study was to determine the accuracy of range-of-fire estimates in shotgun pellet patterns at fixed intervals. It was also of interest to investigate the effect of barrel and shell temperature changes on the diameter of pellet patterns. One hundred shots were fired from a .12 gauge shotgun though a series of 5 in-line paper targets positioned at 5-foot intervals between 15 and 35 feet from the muzzle. A series of confidence intervals was calculated to determine the error in range-of-fire estimates. Statistical analysis of the data revealed that shell but not barrel temperature significantly reduced pattern diameter.

The presence of extraneous markings on a fired bullet that has ricocheted off water depends on the angle of incidence of the bullet to the water and the depth of the water. An Uzi submachine gun, held in a machine rest, was fired into a large container of water at various controlled angles. The angle of incidence and the angle of departure of the bullet from the water were measured. The critical angle of ricochet, the depth of penetration, and the path of the bullet in the water were measured. The measured critical angle of ricochet of a 9-mm parabellum bullet fired from the above weapon was 6.5°. The maximum depth of penetration into the water during ricochet was found to be 22 mm. The maximum track length in the water was 62 cm.

Four cases of homicide, in which silenced firearms were used, are reported and supplemented by data from experimental investigations regarding wound features, marks, traces, and ballistic behavior. Wound features are largely determined by the construction of the silencer. In one case, even a muzzle imprint was produced by a silenced weapon fired at contact range. In general, silencers are likely to result in a decrease in bullet energy and accelerated energy release in the target (tissue). In terms of wound morphology, silencers produced a reduction in or even a lack of the contact ring (ring of dirt). In close-range and contact wounds, any features indicative of shots fired at close range were missing (such as soot deposit and powder tattooing). It is also worth mentioning that biological matter may get into the silencer in shots fired at contact range.

Recently marketed PMC (Pan Metal Corporation) Ultramag tubular hollow point ammunition is uniquely constructed with a two-part projectile composed of a tubular copper bullet and a Teflon wad. A fatal gunshot wound with this ammunition is described. A unique radiographic pattern and the results of test firing are also presented.

This paper reviews the use of trace evidence recovered from spent bullets in helping to establish trajectories. The use of information derived from such trace evidence combined with that from geometrical techniques of trajectory reconstruction and other data is discussed. Five cases are reviewed in which the analysis of trace evidential materials adhering to bullets was used to help reconstruct the event.

The Accelerator® cartridge is unique in that the bullet has no barrel markings after it is fired. The plastic sabot does have barrel markings and can produce distinctive wound patterns. The .30-′06 Accelerator cartridge was fired into poster board, gelatin blocks, and pigs. The results of these studies are presented.

It was determined that tempered glass automobile windows may severely influence the trajectory of .38 Special projectiles. In replicating an actual case situation, deflections as great as 26.4 degrees were observed with jacketed hollow-point ammunition, and as high as 10.8 degrees for lead ammunition.

Multibullet cartridges are used to create the salvo effect with increased hit probability and wounding capacity. These cartridges are not new; however, until recently, their usage has been confined to the military. The following report is the first published case concerning homemade duplex (double-bullet) cartridges manufactured in the Greater Miami area. When gunshot wound entrance and exit sites do not add up, multibullet cartridges must be considered.

This study of Winchester Silvertip® hollow point ammunition measures bullet velocity from production handguns and evaluates performance in ordnance gelation. Depth of penetration, size and shape of the temporary cavity, degree of radial fissuring along the missile track, and bullet expansion after impact are compared to nonhollow point ammunition of similar caliber. It is clear that hollow point bullets of this type create greater disturbance upon impact with tissue simulant than common commercial solid round nose ammunition as measured by temporary cavity size and radial fissuring. However, for all types of handgun ammunition there is a poor predictive correlation of radial fissuring with instantaneous temporary cavity size. Hollow point performance can be modified by various factors such as angle of incidence relative to target surface and prior deformation of the bullet tip. The elemental composition of bullet jackets and cores is not uniform throughout this product line.

This is a study of commercially available .22 caliber rimfire ammunition manufactured to explode on bullet impact. Factors considered were bullet velocity, angle of impact, missile deformation, and depth of penetration and cavitation in ordnance gelatin. Microscopic, radiographic, and high speed motion picture photographic techniques were employed. This study found that the angle of impact was critical for detonation of the bullet.

The unique shape and ballistics aspects of a new variety of hand-reloadable ammunition manufactured by the United States Ammunition Co. are described. The thin copper plating of the projectiles will usually be lost after the weapon is fired. As a result, specific rifling marks will usually be lost, making identification difficult. The medical examiner should be aware of the implications of finding these projectiles during death investigations.

This is the second edition of this book about firearms and the effects of firearms. It is divided in three main chapters: (1) ballistics, weapons, and ammunition; (2) medical consideration of firearms; and (3) criminalistic consideration of firearms. A fourth chapter includes tables and formulas relevant to the subject.

A study was conducted with a 12-gauge shotgun having a 508-mm (20-in.) cylinder-bored barrel firing 00 buckshot. This type of weapon and shot are commonly used by law enforcement agencies. Sheets and plates of steel were used as intermediate targets. A series of shots was fired at close range at angles of incidence below 35° Illustration board, a readily penetrable material, was used as a final target to record the shot pattern of the ricocheted shotgun pellets. The angles of incidence and of ricochet were determined trigonometrically for each round fired. The horizontal and the vertical dispersals of each shotgun pellet were also calculated. The results obtained are compared with those reported by McConnell et al for intermediate targets of concrete road surface material and concrete patio block.

Evaluation of the diameter of a bullet which caused an entrance hole by measuring the diameter of the color rings developed through use of the bullet hole identification kit (BTK) is presented. A direct estimation of the diameter of the bullet can be made, or a range of diameters can be determined. This range depends on the material of the target, and to an extent, on the kind of support behind the target. In the case of woven cotton textiles, this range was found to be small, and larger in other textile materials. Even in these latter cases, one can discriminate between the large and small diameters (for example, those of the 0.22 and 0.38 calibers). These results can be very useful when targets are dark colored or soiled to a degree where the black ring (“ring of dirt”) around the entrance hole is unrecognizable.

A twelve-parameter classification system for jacketed sporting rifle bullets that allows the examiner to gather and record systematically data that can be used to identify the manufacturer, design, weight, and cartridge loading of damaged and intact bullets is presented. The twelve parameters are an identification number, manufacturer, weight, diameter, cartridge, base design, length of bearing surface, color, shape, location and description of crimping cannclure, location and description of other cannelures, and miscellaneous notes.

In a criminal case, police alleged that a gouge in a plaster wall was the result of a bullet ricochet. Experimental studies showed that it is possible to obtain bullet ricochets from gypsum wallboard if the bullets are fired at a very low angle of incidence into the wallboard. The resulting ricochet marks, however, did not resemble the gouge alleged to have been caused by a bullet ricochet. When the angle of ricochet was determined, it was in all cases greater than the angle of incidence. While these results differ from those obtained in studies of ricochets from concrete and metal plates, they are similar to the results obtained in studies of bullet ricochet from soil and water.

Test shots were fired into real and simulated automobile ceilings in an attempt to determine what types of evidence should be available for determining the direction of flight of the bullet. The information obtained was used in a shooting investigation.

The authors report two cases in which examination of foreign material embedded in or adherent to bullets provided critical information in the reconstruction of a crime scene. Analysis of small particles by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDXA) can be accomplished without destruction or injury of the particles. In one case, the detection and identification of mineral fragments embedded near the nose of a bullet provided conclusive evidence that the bullet had ricocheted from a fireplace before striking the victim. In the second case, analysis of particles from two bullets identified them as them as bone fragments, thus proving which shots fired from a police officer's gun had killed a suspected burglar. SEM-EDXA has not been widely used to identify such material on bullets, but should be considered a potentially powerful tool in forensic science.

Small angles of projectile entry are difficult to determine in two-dimensional targets or in three-dimensional targets where internal deflection has taken place. This results from the fact that small errors in measurement lead to large errors in the calculation of the sine function used in the estimation of the angular projection of a circle onto an inclined plane at angles of less than 20° from the normal. The use of a bullet tip scale, constructed to the dimensions of the entering projectile, allows a significantly more accurate determination of small angles of entry in targets not subject to stretching. A comparison of the relative error inherent in calculating entry angle using the sine function and measuring the angle using the bullet tip scale demonstrates the suitability of using the tip scale at angles less than 20° and the sine function at entry angles greater than 20°.

Great controversy has surrounded the replacement of the 7.62-mm caliber by the reduced 5.56-mm caliber as the standard U.S. military rifle. Although its relevance to human wounding can be debated, the terminal ballistics of military small arms in ordnance gelatin remains a convenient medium for comparative testing. In the present study, 7- by 10- by 24-in. (18 by 25 by 61 cm) blocks of 20% ordnance gelatin were fired upon from a range of 19 ft (6 m) under high-speed cinemagraphic surveillance. The tendency of the M193 5.56-mm full metal jacket projectile to break up in soft tissue simulant was confirmed as a fundamental difference from the 7.62-mm M80 NATO ball.

A field kit for the identification of bullet holes using chemical spot tests for lead and copper was used in an investigation of an accidental wounding during a military exercise. Based upon the results obtained using the kit, it was possible to detect the bullet holes in question, and thus, reconstruct the path and direction of the bullet. It was further possible to estimate the type and diameter of the bullet.

The effects of water-soaking on firing distance estimations, employing quantitative determinations of gunpowder and metals around the bullet's entrance hole, were studied. The main finding was that, since the precision of the quantitative determination is poor, the existing statistical spread cancels out a potential effect of the target soaking. None the less, the prevailing factor is the firing distance, where increments of about 25 cm are clearly distinguishable, in both dry and water-soaked targets.

Air and spring actuated guns firing spherical or elongated projectiles are widely used for target practice and pest shooting. Although their ability to inflict physical injury is well recognized, the fact that some of these guns are potentially lethal is surprising to those not familiar with their history and ballistics. The Austrian armies, for example, used air rifles against the French during the Napoleonic wars of 1799–1809 [1]. These were rifles of 12.8-mm (1.50-in.) caliber and had an effective range between 100 and 150 yards (91 and 137 m). An air rifle of unknown caliber was also carried by the Lewis and Clark expedition of 1804–1806 [2] and was used on occasion to kill deer-size animals as well as birds and small game.