Maximum range of pellets fired from a shotgun

A mathematical model to determine the maximum range of pellets fired from a shotgun has been suggested. It has been assumed that the air resistance experienced by a pellet is proportional to the square of its velocity (?μV²) where $\text{μ =}\text{A}\text{C}$ with

$\text{C=0.061}\text{86}\text{N}{}^{\mathrm{<mtext>1</mtext><mtext>3</mtext>}}$

and

$\text{A=}\text{1}\text{[17 696+2N+10 000(0.2?d)]}$

N is the number of pellets/ounce and d is the diameter of the pellets in inches. A method for calculating the maximum range has been suggested, and the values obtained for Buck 00, size 8 and size 9 American pellets are very close to the reported experimental observations. The maximum ranges for other sizes of pellets have also been calculated. The angle of projection decreases with increase in velocity and increases with increase in the weight of the pellet. It varies between 26° to 32° for common sizes of pellets and standard shotgun velocity. The maximum range in air is only 1 – 3% of the range attained by a pellet in vacuum.     

Shot range estimation based on pellet distribution in shots with a pump-action shotgun

In the present study, shots from different ranges were fired using a non-choked pump-action shotgun (Hugsan) of calibre 12 with a bore length of 52cm and pellets of various sizes. The aim of the study is range estimation from the distribution of pellets.Using pellets of 2, 3.5, 5 and 8mm size, 5 shots were fired from: 0.7, 0.8, 0.9, 1, 2, 3, 5, 10, 15, 20 and 25ms. The maximum distance between the pellets in vertical and horizontal direction was measured. Statistical evaluation of the data revealed a highly significant correlation for each pellet type; the constant values a and b were calculated to be used in the linear regression equation y=a+bx.As a conclusion, the linear regression equation as well as table data may allow range determination within acceptable ranges of error for the same barrel length and diameter for the same cartridge type. Under identical conditions they may also provide information for pellets of comparable size.     

Shotcup petal abrasions in close range .410-caliber shotgun injuries

Shotcup petal abrasions centered around a shotgun wound of entrance are generally thought to occur at a range of 30 to 90 cm. A suicidal .410-caliber shotgun injury of the right eye is described in which typical petal abrasions were noted around the entrance wound. However, significant soot deposition around the wound suggested that the range of fire was less than 30 cm and perhaps closer to 15 cm. Test-firing of the weapon and ammunition used by the decedent showed some spread of the shotcup petals at a range of 7.5 cm, progressing to maximum spread at 30 to 52.5 cm. Further testing with other .410 ammunition, containing shotcups, confirmed the spread of shotcup petals at ranges less than 30 cm, irrespective of manufacturer, shotshell length, and birdshot size. When a variety of shotguns were tested, it was found that one weapon with a very short barrel and cylinder bore did not exhibit petal spread until a range of 30 cm was reached. The remaining shotguns, with longer barrels and full choke, all demonstrated definite petal spread at a range of 12.5 cm. The long, narrow configuration of .410 shotcup petals may explain their early spread and the production of petal abrasions at ranges of less than 30 cm.     

Test-extractor marks under low pressure on shotgun cartridges

The necessity for firing high pressure test rounds to imprint extractor marks on shotgun cartridges in cases involving improvised or non-standard locally made firearms has been obviated. A suitable method for obtaining desired extractor marks on shotgun cartridges under low pressure has been suggested.     

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。     

Time since discharge of shotgun shells

A technique for the estimation of time since discharge of a given class of spent shotgun shells is presented. The technique involved the use of SPME (Solid Phase Microextraction) sampling from the atmosphere inside spent shotgun shells. Compounds absorbed on the SPME fiber were desorbed and analyzed with GC-MS. The decrease in concentration of the combustion product naphthalene was monitored in all shells over a two-month period. Three conditions were examined to prevent naphthalene from escaping prior to testing the shells. A glass vial was successfully incorporated to halt the dissipation of naphthalene. At room temperature the naphthalene peak can be measured for several months and the curve-fitting data can lead to an estimation of time since discharge.     

A distant-range, suicidal shotgun wound of the back

The case being reported is one of a shotgun fatality with a thoracic back wound. A 23-year-old man was shot from a distance with trajectories going from back to front and on a nearly horizontal level. These findings observed in the autopsy could represent homicide, but scene investigation and police records were interpreted and it became clear that the case was suicide. Thus, this case shows that the determination of the manner of death requires a careful forensic investigation including autopsy findings, scene investigation, and reconstruction of the events.     

Multivariate statistical analysis of shotgun pellet dispersion

Shotgun pellet dispersions were measured by using a shotgun with the following parameters being varied: barrel length, discharge distance, choke constriction and shot size. To reduce the number of experiments the statistical technique of Greco-Latin squares was used. A full statistical analysis of the data carried out and possible correlations between dispersion and the parameters examined. No association was found for shot size or barrel length, and little for choke, distance being the only large correlation with dispersion. Dispersion is not a truly linear function of distance and it is probable that another factor has to be incorporated into any mathematical expression for dispersion of shot.     

根据猎枪射击弹壳痕迹判别枪种的研究

对国内6家定点生产的撅把式和唧筒式猎枪进行实验射击,分析了在弹壳上形成各种痕迹的机理及利用价值,提出了根据猎枪射击弹壳痕迹判别枪种的方法。     

The effects of various intermediate targets on dispersion of shotgun patterns.

Intermediate targets cause dispersion of a shot pattern by a ricochet effect. Thus, the intermediate target must have sufficient thickness or tensile strength to slow down the initial group of shot striking the target. Aluminum and steel screen, ordinary window glass, thin cardboard and thin cowhide did not manifest these qualities under the conditions of these experiments.     

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.     

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.     

The effect of tempered glass on bullet trajectory

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.     

An evaluation of distribution of pellets due to shotgun discharge

Dispersion of pellets due to shotgun discharge has been considered in terms of a Gaussian distribution. Only approximate results are obtained in forensic ballistic cases, but when these are compared with the empirical findings of Burrard, they are found to be reasonably satisfactory. Limitations of the model are discussed.     

Unusual motor ability in gunshot injury of the heart caused by a shotgun

In a case of shotgun-injury of the heart with complete rupture of both ventricles and lesion of the aorta the victim was able to move a few metres in approximately six seconds. Despite other opinions ability to move or act can be maintained in cases of severest injuries of the heart caused by missiles with high energy.     

Unusual shotgun injury. Gas blowout of anterior head region

During a 6-month period, we encountered two examples of tight contact wounds of the temple region which were associated with ovoid, fairly regular, perforating wounds of the skull and overlying skin. These wounds were located between the eyes with the upper border near the glabella and the lower border near the level of the lower eyelids. There was no evidence that these wounds were entry wounds and in both cases the projectiles were still within the cranial cavity. Therefore, they were interpreted as gas blowout wounds. No similar cases have been found in the literature. Law enforcement personnel and pathologists should be aware of this rather rare blowout type of shotgun injury since it may be subject to various misinterpretations, including that of an entry wound.     

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.