A new type of shotgun ammunition produces unique wound characteristics

The Tucson Police Department, Tucson, AZ, has begun using the Polyshok Impact Reactive Projectile (IRP), a new type of shotgun ammunition that includes a lead bead core that travels within single, plastic-encased projectile. On impact, the core is released to distribute over a small area, thereby disintegrating on impact to reduce the likelihood of exit or collateral damage on missed shots. After a brief review of shotgun slug ballistics and wound characteristics and a discussion of the mechanism of the Polyshok IRP, we report the first death in the United States from this ammunition. Findings included a single entrance wound with plastic ammunition components and small lead particles recovered from the body, the combination of which normally would suggest a close-range shooting with birdshot. However, the characteristics of this ammunition create different patterns than are found with slugs or shot, so that a medical examiner unfamiliar with the Polyshok IRP could draw inaccurate conclusions about ammunition and range of fire. Because the single projectile fired from this ammunition is composed of both plastic and lead, plastic components are likely to be found within the wound at any range of fire, unlike traditional shot or slug ammunition. Also, the small size of lead particles found spread through the wound cavity would ordinarily suggest a small-size shot, whereas the external appearance of the wound (a single entrance with no dispersion of shot) and the pattern of tissue destruction are more consistent with the patterns of injury associated with shotgun slugs.     

Gunshot injury caused by a training bullet]

In the course of a scuffle a 50-year old man has been shot by a revolver. The culprit and witnesses state, there has been only one shot, whereas the victim declared having been shot twice. The medico-legal investigation revealed a gunshot wound that passed through the left thigh, a grazing shot of the right hand and a superficial lesion of the skin at the forehead with sprinkled gunshot residue in the epidermis. The investigation confirmed the statement of the victim: the first shot to the forehead was caused by a plastic training cartridge, the second to the right hand and thigh by a cartridge loaded with an ordinary bullet.     

Entrance, exit, and reentrance of one shot with a shotgun

The case being reported is one of a homicidal shotgun fatality with an unusual wound pattern. A 34-year-old man was shot at close range with a 12-gauge shotgun armed with No. 5 birdshot ammunition. The shot entered the left axillary region, exited through the left infraclavicular region, and thereafter penetrated the left side of the neck, causing tearing of the left common carotid artery and the right internal carotid artery. The entrance wound in the axilla was larger than the other wounds, and before autopsy it was believed that the shotgun had been fired twice, causing one wound in the neck and one wound perforating the infraclavicular region and exiting through the left axillary region. Thus, this case shows that unusual wound patterns in shotgun fatalities can easily lead to incorrect assumptions with regard to number and direction of shots fired unless thorough investigation is carried out postmortem.     

Pellet embolization to the right atrium following double shotgun injury

A 28-year-old man sustained two shotgun injuries of the left inguinal region from a distance of about 1.5 m by simultaneous discharge of both shells from a sawn-off double-barrelled 16-bore shotgun (diameter of the lead pellets, 4 mm). The first X-ray examination carried out soon after hospital admission showed a single embolized pellet near the right margin of the cardiac silhouette. Eight months later, the man committed suicide by drug intoxication. At autopsy, the embolized pellet was found embedded between the pectinate muscles of the right atrium. On the basis of the reported case and with reference to the pertinent literature, the paper points out the medico-legal aspects of venous bullet/pellet embolism and the risk of lead poisoning after shotgun injury.     

Pump-gun as a weapon. Type of injuries, prohibition of weapons

Pumpguns are shotguns with pump action whose injuries and wound mechanisms have several special features: extremely high kinetic energy of the shot (2500 to 3500 J) frequent cases of "Kr?nlein shots" (exenteration of the brain) punchmark/imprint immediately adjacent to the entrance wound from the front of the pipe magazine exit wounds from buckshot may be similar to pellet entrance injuries from a distant shotgun discharge the use of various shotgun cartridges (plastic ammunition, slug bullet, various lead pellets) within the same weapon. The change in the Austrian gun law and the banning of the pumpgun in 1995 is also discussed in the article.     

Relation of Kinetic Energy to Contact Wounds of the Head by Centerfire Rifles and Shotgun Slugs

Wounds of high‐energy centerfire rifles and shotguns represent distinctive injuries of forensic importance. Previous studies of contact wounds have shown variability in the potential of these weapons to produce bursting wounds of the head. The present study analyzed contact head wounds owing to 26 centerfire rifles and nine shotgun slugs and compared them with respect to weapon, ammunition, entry wound site, and projectile kinetic energy. The bursting effect, defined for this study as disruption of at least 50% of the head, occurred in 25/35 of cases and was related to kinetic energy. Bursting was associated with energies <2700 ft‐lbs in 12/22 cases and energies >2700 ft‐lbs in 13/13 cases. The volume of gunpowder gas injected into the wound was considered as contributing to the bursting phenomenon. There was no relation of bursting to the specific entrance wound site, type of ammunition, or projectile fragmentation.     

霰弹弹杯所致损伤及其应用价值

本文17例制式霰弹猎枪射入口和创道的病理形态学，通过结合射击实验获得了较为一致的结果。初步认为，商品霰弹中的塑料弹杯所造成射入口创缘或创周损伤的形态变化与射击距离密切相关，在法医学鉴定中具有一定的应用价值。     

Suicide,accident? The importance of the scene investigation

We present the as yet unresolved case of the death by gunshot wound of a 21-year-old student from a recent local inspection. It was reported that the daughter of the house had been shot through the window while she was washing the dishes. Slight discrepancies were noted in the statements of the family, who are very religious. The firearm, projectile and cartridge have not been found despite an intensive search. The daughter and the mother tested positive for traces of gunpowder on their hands, while in the case of the son traces were found on his hands and on his vest. That the trajectory of the projectile was from the kitchen outwards was established on the basis of a small hole in the inner pane of the kitchen window and a larger hole in the outer pane. The shot passed through the victim's cheek and the neck. The entrance wound (aditus) on the right cheek had complementary features characteristic of a gunshot from a short-barrelled firearm at relative proximity. The shot passed through the left jugular vein and the left internal carotid artery. The exit wound (exitus) was slightly larger and of irregular shape.The family chose a traditional burial. The mother and son did not present themselves for polygraph testing. A charge was filed against the mother of the deceased. Emphasis was placed on the scene investigation.A covered-up suicide? An accident (a scuffle when trying to prevent suicide)?     

Estimating Projectile Perpendicular Impact Velocity on Metal Sheet Targets from the Shape of the Target Hole

Abstract:  The correlation between bullet hole shapes in metal and projectile impact velocity was examined. A series of shots were fired from an M-16A1 assault rifle of 5.56 mm caliber toward a 1-mm thick metal target. All shots were fired at a perpendicular angle to the metal sheets, and the velocity was measured just before the projectile hit the target. Velocities ranged between 400 and 900 m/sec. From the replica of the shooting hole, a perpendicular plane was created, showing the symmetrical properties of the hole. The best mathematical equation describing the shape of the entrance hole was the exponential function in the form:
The empirical equation of the hole defined using the regression method is:
This equation describes the general shape of shooting holes created by velocities ranging from 440 to 750 m/sec. From this equation, one can estimate the bullet velocity when it hits the target.     

Popliteal artery bullet embolism in a case of homicide: a case report and review of the tangible literature

Bullet embolism is a well known but a relatively rare phenomenon in common medicolegal autopsy practice. We present a homicide case of a bullet embolism to the left popliteal artery with interesting trajectory of projectile through the chest wall and right heart ventricle into the aortic lumen. Since in our presented case obvious homicidal manner of death was in question, discovery of bullet was an obligatory part of investigation in order to positively identify the responsible firearm. Detection of the missile transported through the circulation requires very thorough autopsy examination, especially if X-ray equipment is not available. As in all other cases in which initial bullet trajectory is changed in the body, the very important part of the medicolegal autopsy in cases accompanied with missile embolism, is to determine direction of the first part of the bullet's trajectory, because this indicates the position of the axis of the weapon barrel in the moment of firing (if there was no external ricochet), taking into consideration the posture of the victim and the location of the shooting person in the same moment. A review of the tangible literature is given.     

Case Report of a Migrating Bullet: An Unusual Cause of Postmortem Confusion

Migrating bullets are rare sequelae of penetrating gunshot wounds. Such cases have been described in the neurosurgical literature because they can produce complications in the management of patients such as decline in neurologic status, delays in rehabilitation, and difficulties in bullet removal. In contrast, few postmortem reports have described this phenomenon. We report a case of a gunshot wound in which the projectile entered the left side of the head and traversed to the right frontal area as documented by CT scan on hospital admission. At autopsy, the bullet was noted to have migrated back to the left side of the head from where it was recovered. Medical examiners need to be aware of this unusual phenomenon of retained intracranial projectiles.     

Ballistic characterization of the Remington Premier Copper Solid sabot shotgun slug

We evaluated the impact and penetration characteristics of the Remington Copper Solid sabot shotgun slug with standardized ballistic tests and used this information to predict tissue wounding patterns. This unique ammunition, first distributed in 1993, is composed of a solid copper, hollow-point slug with longitudinal slots cut into the nose. The slug is fitted into a hard plastic sabot with 8 finger-like projections and loaded into a shotgun shell with two plastic wads separating it from the underlying gunpowder charge. The ammunition was fired through a 12-gage shotgun using a rifled barrel, a smooth-bore barrel with rifled choke, and a smooth-bore barrel with a smooth modified choke into targets consisting of poster board and 10% ballistic gelatin at a variety of distances. The copper slug and plastic sabot created single 8-fingered asterisk-shaped defects in the poster board when fired at distances of less than 7 to 9 ft (approximately 2 to 3 m). All three barrel types performed similarly. At greater distances, the sabot impacted the targets separately from the slugs and created variably shaped defects that reflected base-first, nose-first, and side-first impacts. Increasing muzzle-to-target distances generally increased the impact distances between the slug and sabot. There was no predictable relationship between the sabot and slug impact points for any of the three barrel types. With each barrel tested, the wads created separate defects from the slug at distances greater than 5 ft (1.5 m). The distances between the slug and the wad impact points increased with increasing muzzle-to-target distances up to 40 ft (12 m), after which the wads generally no longer struck the targets. The slug created atypical defects at distances between 7 and 150 ft (approximately 2 to 45 m), probably due to yawing or tumbling. When the slug impacted the gelatin block in a nose-first orientation, the slotted nose portion tended to fragment and radially deposit pieces in the gelatin that were visible on radiographs. When the slug struck the gelatin target in a side-first orientation, it passed through the gelatin intact. The slug, sabot, and wads of this unique projectile separate and create independent impact points in a stereotypical manner independent of barrel type. This pattern of separation allows estimates to be made of ranges of fire. Wounds created in human tissues by this ammunition would likely have similar asterisk-shaped configurations, and nose fragments may be deposited in tissues and seen radiographically. Rectangular wounds created by the tumbling or yawing slug might be mistaken for intermediate target wounds.     

差示扫描量热法检验猎枪弹丸

目的对不同厂家的猎枪弹丸进行区分和鉴别。方法使用功率补偿型差示扫描量热仪(DSC)对4种不同品牌的猎枪弹丸进行分析。结果可测得每种弹丸的DSC曲线和熔点温度Tm,熔融峰温Tmp,熔化焓ΔHm等热学参数。结论利用差示扫描量热法可以对不同品牌的猎枪弹丸进行鉴别,该方法为办案过程中遇到同号数不同品牌的猎枪弹丸鉴别提供了一种有效技术手段。     

Intravascular bullet embolism to the right atrium

Bullet embolism is a relatively unusual complication of gunshot wounds. Embolism to the right atrium comprises <5% of all reported intravascular bullet emboli. We report an additional case of bullet embolus to the right atrium of a 0.38-caliber bullet following a gunshot wound to the chest. The intracardiac bullet was recognized radiologically on presentation, but the patient was hemodynamically stable and managed conservatively, with the bullet left in place. The missile remained within the heart without clinical significance for several years and was recovered from the right atrium only at the time of autopsy. To the best of our knowledge, this is the first documented case of a 0.38-caliber bullet which embolized to the right atrium and remained inconsequential for an extended period of time.     

Suicide by a power drill

This is the report of a 62-year-old man who committed suicide by drilling through his anterior chest wall with an electric power drill. Death was caused by pericardial tamponade combined with bleeding into the pleural cavity. The skin lesion at the left hemithorax was similar to a bullet entrance wound.     

Suicidal single gunshot injury to the head: differences in site of entrance wound and direction of the bullet path between right- and left-handed--an autopsy study

The aim of this study was to determine the differences in the anatomical site of a gunshot entrance wound and the direction of the bullet path between right- and left-handed subjects who committed a suicide by a single gunshot injury to the head. The retrospective autopsy study was performed for a 10-year period, and it included selected cases of single suicidal gunshot head injury, committed by handguns. We considered only contact or near-contact wounds. The sample included 479 deceased, with average age 47.1 ± 19.1 years (range, 12-89 years): 432 males and 47 females, with 317 right-handed, 25 left-handed, and 137 subjects with unknown dominant hand. In our observed sample, most cases involved the right temple as the site of entrance gunshot wound (about 67%), followed by the mouth (16%), forehead (7%), left temple (6%), submental (2%), and parietal region (1%). The left temple, right temple, and forehead were the sites of the gunshot entrance wounds, which were the best predictors of the handedness of the deceased (Spearman ρ = 0.149, P = 0.006). Our study showed that the direction of the bullet intracranial path in cases of suicide was even a more potent predictor of the handedness of the deceased (Spearman ρ = 0.263, P = 0.000; Wald = 149.503, P = 0.000).     

Multiple suicidal gunshots to the head

We report two cases of suicide by multiple gunshots to the head. The first victim (of two shots) fired the first shot, which was observed, into his mouth, leading to damage to the left optic nerve and frontal lobe. The man still was able to drive his car home, where he shot himself in his right temple. He died 2 days later. The second victim (of three shots) was a 58-year-old man who was found dead on his bed. Reconstruction of the case disclosed that the first shot had passed through his tongue and slightly damaged the second cervical vertebral body. He then shot himself in his right temple, leading to damage of the temporal lobe. Finally, he shot himself in his left temple, resulting in destruction of the pons. In the first case, an amateurishly modified 8-mm blank revolver firing 6.35-mm- (.25)-caliber ammunition was used; in the second case, a rifle firing 5.6-mm (.22)-caliber ammunition with a reduced charge was used. In both cases, low-energy transfer to brain tissue by the initial bullets was due to low bullet energy or due to the bullets' missing the brain or vital centers.     

Confusing injury findings in a suicidal gunshot fired to the chest from a carbine with a sawed-off barrel

The stellate bullet entrance wound is one of the facultative features of a contact shot. For the formation of a star-shaped wound two factors are of special importance: first, an extensive bony support underlying the skin in the entrance region, and second, a strong propellant charge of the cartridge fired. Contact shots to the precordial region usually do not cause stellate entrance wounds, even if high-powered rifle ammunition is used. In the reported case, an injury pattern was observed that was not in line with normal findings and seemed confusing at first. Following a suicidal gunshot to the chest from a sawed-off carbine 98a (cal. 8 x 57 Js), a 4.5 cm wide, gaping bullet entrance wound with radiating tears was found. Instead of the usual pocket, the anterior thoracic wall showed a fist-sized area of destruction with extensive undermining of the subcutis. Not far from the entrance hole, a rib fragment had become displaced retrogradely thus perforating the skin from the inside out. The unusual pattern of findings could be explained by the fact that the barrel had been sawed off: as a result of this manipulation, a considerable part of the propellant charge had been converted outside the barrel, i.e. in the initial section of the bullet path.