Firearm Wounds in Animals

Firearm wounds in animals generally produce two wounds or apertures. One of entrance and the other of exit of the projectile. The wound of entrance is usually smaller than the projectile because of the elasticity of the skin, and is round when the projectile strikes the body at right angles and oval when it strikes obliquely.

Types of Firearms

Shotguns

Shotguns fire a number of shots together, with barrels varying in size from 22 to 30 bore are smooth inside and are commonly used to kill birds and small animals. An average shotgun cartridge varies in size from 2 to 3 inches. Ordinarily shotguns are effective within a range of thirty to forty yards.

Rifled Firearms

Rifled firearms are firearms which fire a single bullet and have one barrel only. These have firing range of upto 1000 yards and can cause serious or fatal injury to man or animals.

Firearm Wound

Firearms generally produce two wounds or apertures, viz., one of entrance and the other of exit of the projectile. The wound of entrance is usually smaller than the projectile because of the elasticity of the skin, and is round when the projectile strikes the body at right angles and oval when it strikes obliquely.

When a wound of entrance is present, but not the wound of exit, it means that a bullet is lodged in the body, except in those cases where the bullet has been coughed up after entering the respiratory passages or lost in the stool after entering the intestinal tract and also when a hard bullet coming in contact with a bone is so deflected as to pass out through the same orifice by which it entered.

If a bullet is lodged in the body it must be taken out if death has occurred, and forwarded to the Superintendent of Police in a sealed envelope containing its description in the Veterinary Officer’s handwriting as it forms evidence of the greatest value.

While searching for a bullet it must be borne in mind that it may take a very erratic and circuitous course while passing through the body. In a case where death has not occurred, the bullet should be located by means of X-ray, if possible.

The flame and the forceful expansion of the gases of explosion in the skin and subcutaneous tissues usually cause a large entry wound, the edges of which are ragged and everted. Wadding or debris maybe found lodged in the wound with the skin surrounding it being scorched and tattooed with particles of unconsumed gunpowder.

The entry wound of a revolver fired very near or in contact with the skin is stellate or cruciform in shape instead of being circular. When it is fired from beyond a distance of 12 inches, there are no gunpowder marks around the wound.

If the revolver is fired close to the skin but held at an angle, the smudging and tattooing is limited only to one side of the bullet hole. The wound of exit is often larger than the wound of entrance, and its edges are irregular and everted, but free from scorching and tattooing. The edges of both the wounds of entrance and exit may be everted in fat animals due to protrusion of fat into the wounds, and in decomposed bodies because of the expansible action of the gases of putrefaction.

The edges of the wound of exit may be very ragged and torn, if the projectile was discharged at close quarters, had passed through the bone or was deformed by striking elsewhere first (wound by recoil). These characters of the wound are due to the wobble of the projectile, its deformed condition, laceration of the skin by fragments of bone expelled from the body along with the projectile or by the splintered pieces of the projectile itself.

Large bullets cause greater damage to the internal organs than small ones. Round bullets produce larger wounds than conical ones. They cause extensive laceration of the tissues and comminuted fracture of the bones if ‘hey strike the body at a different angle and sometimes their course is arrested by coming in contact with chains or other hard articles.

Conical bullets produce much less laceration than round ones, and the rounds caused by them are punctured in appearance. Conical bullets rarely split in the tissues, though round ones often do.

Modern, steel-jacketed bullets used in army weapons have the shape of an elongated cone and owing to their great velocity usually pass straight d directly through the body without any deflection or deviation, and without causing much damage.

The wounds of entry and exit are almost circular and similar in appearance, without any bruising or laceration of the surrounding parts. Such wounds heal very rapidly.

Even wounds caused by such bullets in the brain, lungs, or intestines often run a perfectly normal course, and heal without any difficulty. Expanding, grooved, dumdum bullets are very destructive and produce extensive wounds with ragged margins.

Fragments of shell are also destructive and cause extensive wounds. Irregular missiles, such as pieces of stone, iron, kankar, beads of brass or nickel anklets or wristlets, seeds etc. used in muzzle-loading guns produce several irregular, lacerated wounds, and the exit wounds are larger than the entrance wounds.

It is possible for a single pellet or shot to cause death. Wadding or gunpowder may cause laceration and may produce death by penetrating the internal organs of the body, even if a blank cartridge is discharged close to the body.

Velocity of Projectile

A bullet travelling at high velocity produces a clean, circular, punched-out aperture or slit, as in a stabbing wound, and usually perforates the body.

It is not deflected from its path by striking a bone, but may cause its comminution or splintering. On the other hand, a bullet of low velocity causes contusion and laceration of the margins of the wound of entrance.

It is easily deflected and deformed by striking some hard object, and often lodges in the body.

The track made by a bullet widens as it goes deeper. This is the reverse of a punctured wound. If a bullet grazes a bone, it may produce a gutter, with or without fracturing it, and may or may not give the direction or deflection of the bullet.

Distance of Firearm

If a firearm is discharged very close to the body or in actual contact with it, subcutaneous tissues over an area of two or three inches round the wound of entrance are lacerated and the surrounding skin is usually scorched and blackened by smoke and tattooed with unburnt grains of gunpowder.

If the gunpowder is smokeless there will be no blackening of the skin, but there may be a greyish or white deposit on the skin around the wound. No blackening or scorching is found, if the firearm is discharged from a distance of more than four feet.

Moreover, these signs may be absent even when the weapon is pressed tightly against the body, as the gases of the explosion and the flame, smoke and particles of gunpowder will all follow the track of the bullet in the body. The effects produced by small shot fired from a shotgun vary according to the distance of the weapon from the body, and the choking device.

A charge of small shot fired very close to, or within a few inches of, the body enters in one mass like a single bullet, making a large irregular wound with scorched and contused edges, and is followed by the discharge gases which greatly lacerate and rupture the deeper tissues.

Particles of unburnt powder expelled from the weapon behind the missile are driven to some distance through the wound, and some of them are found embedded in e wound and the surrounding skin which is also singed and blackened by the flame and smoke of combustion.

The exit wound of a close range shows greater damage to tissues than the entrance wound, the margins everted, but there is no evidence of blackening or singeing.

At a distance of one to three feet small shot make a single aperture with irregular and erated edges corresponding in size to the bore of the muzzle of the gun, as the shots enter as one mass, but are scattered after entering the wound and cause great damage to the internal tissues.

The skin surrounding the wound is blackened, scorched and tattooed with unconsumed grains of powder. On the other hand, at a distance of six feet the central aperture surrounded in an area of about two inches in diameter by separate openings made by a few pellets of the shot which spread out before reaching mark.

The skin surrounding the aperture is not blackened or scorched, but is tattooed to some extent.

At a distance of twelve feet the charge of shot spreads widely and enters the body as individual pellets producing separate openings in an area of five to eight inches in diameter, but without causing blackening, scorching or tattooing of the surrounding skin. As the distance increases, the damage caused by a single pellet diminishes, until at about 30 feet, it is only capable of penetrating the skin of an animal.

Time of Firing

After recent discharge a black deposit of potassium sulphide mixed with carbon is found in the barrel of the firearm, if black gunpowder was used. Up to five or six hours this deposit forms a strongly alkaline solution when dissolved in distilled water and emits an offensive odour of sulphuretted hydrogen.

If the solution is filtered, and the filtrate is treated with a solution of lead acetate, a black precipitate of lead sulphide is formed. After exposure to air and moisture for a few days the potassium sulphide becomes converted into thiosulphate, thiocyanate and finally potassium sulphate, that gives a neutral solution with distilled water that gives a white precipitate with lead acetate. Later, oxides of iron (iron rust) with traces of iron sulphate are formed in the barrel.

Smokeless nitro-powders leave a dark grey deposit in the barrel of a recently discharged firearm. It does not change with the lapse of time, gives a neutral solution with distilled water, and contains nitrites and nitrates, but not sulphides. If chromate or bichromate powder is used, the residue in the barrel is usually of a greenish tint.

It should be borne in mind that the composition of the deposit will vary considerably if the firearm was dirty at the time of its discharge, and a veterinarian has no means to know its condition prior to discharge. Again, a deposit would not be found if the weapon had been thoroughly cleansed after discharge.

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