Intermediate Range Wounds

An intermediate-range gunshot wound is one in which the muzzle of the weapon is away from the body at the time of discharge yet is sufficiently close so that powder grains emerging from the muzzle strike the skin producing powder tattooing; this is the sine qua non of intermediate-range gunshot wounds.

In addition to the powder tattooing, there may be blackening of the skin or material around the entrance site from soot produced by combustion of the propellant. The size and density of the area of powder blackening vary with the caliber of the weapon, the barrel length, the type of propellant powder, and the distance from muzzle to target. As the range increases, the intensity of powder blackening decreases and the size of the soot pattern area increases. For virtually all handgun cartridges, soot is absent beyond 30 cm (12 in.). (For a more detailed discussion of powder soot, see Chapter 4.)

Although soot usually can be wiped away either by copious bleeding or intentional wiping, powder tattooing cannot. Tattooing consists of numerous reddish-brown to orange-red, punctate lesions surrounding the wound of entrance (Figure 5.13). Powder tattooing is due to the impact of unburned, partially burned, or burning powder grains onto and into the skin. Powder tattooing is an antemortem phenomenon and indicates that the individual was alive or at least that the heart was beating at the time the victim was

Figure 5.13 Powder tattooing from disk powder.

shot. If an individual is shot at intermediate range after the heart has stopped beating, mechanical markings will be produced on the skin. These markings, however, will not have the reddish color, i.e., the vital reaction of antemortem tattoo marks. Postmortem tattoo marks have a yellow, moist appearance. They are less numerous than markings produced in the living subject at the same range.

For handguns, forensic textbooks generally have stated that the powder tattooing extends out to a maximum distance of 18 to 24 in. (45 to 60 cm) from the muzzle. Such statements do not take into account the different physical forms of propellant powder. At present, in the United States, handgun cartridges are loaded with four forms of propellant: flake, spherical (true) ball powder, flattened ball powder, and cylindrical powder (Figure 5.14). Ball powder is favored in high-pressure loadings such as the .357 Magnum cartridge—because for consistent homogenous ignition of ball powder, high pressure, and thus high temperature conditions are necessary. In the past, however, ball powder was used for pistol loadings down to the .25 ACP. Some manufacturers use uncoated ball powder for better ignition. Grains of uncoated ball powder are a pale green color.

Flake powder usually is in the form of disks though some foreign manufacturers produce flake powder in the form of quadrangles. Circular disks of flake powder can vary greatly in diameter and thickness. If the graphite coating is lost the flakes have a pale green translucent appearance.

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