Wounds Due to Handguns

"God created men equal. Sam Colt made 'em equal."

Annonymous

Handguns are the most commonly used form of firearm in both homicides and suicides in the United States. Handguns are low-velocity, low-energy weapons having muzzle velocities generally below 1400 ft/sec. Advertised velocities of revolver cartridges traditionally have not been accurate because they are obtained in test devices that have no cylinder gap. Even in well-made revolvers, this gap will cause a velocity loss of approximately 100 to 200 ft/sec, depending on initial velocities and pressure as well as the construction tolerances of the weapon. Advertised velocities for semiautomatic pistols are more accurate as there is no cylinder gap from which gas can escape. The length of the barrel also influences muzzle velocity. The longer the barrel, the greater the velocity. Table 5.1 gives the advertised muzzle velocities of some .22-caliber and .38 Special ammunition compared to the actual velocities determined in revolvers with 2-, 4-, and 6-in. barrels. The velocity of .22-caliber ammunition in a rifle is also given.

The Remington Firearms Company developed a method of measuring the performance of revolver ammunition that reflects ballistic results more accurately. This method involves use of a vented test barrel. The technique takes into account the cylinder gap (controlled at 0.008 in.), barrel length (4 in.), powder position (horizontal), and production tolerances, as well as allowing for reasonable wear and tear.1 Table 5.2 shows a comparison between the ballistic data that Remington previously published concerning its ammunition and the results obtained with a vented test barrel. Significant differences in the results can be seen.

Theoretically, the muzzle velocity in Saturday Night Special revolvers should be less than that in well-made revolvers because of greater tolerance

Table 5.1 Advertised Muzzle Velocities Versus Actual Velocities

Advertised

Muzzle

2-in.

4-in.

6-in.

Cartridge

Velocity (ft/sec)

Barrel

Barrel

Barrel

Rifle

.22 Long rifle

1255

916

1034

1052

1237

.22 Short

1095

851

861

960

1005

.38 Special

855

687

722

765

Table 5.2 Conventional Test Barrel Ballistics Versus Vented Test Barrel Ballistics

Muzzle Velocity

Table 5.2 Conventional Test Barrel Ballistics Versus Vented Test Barrel Ballistics

Muzzle Velocity

Conventional Test

Bullet

Barrel

Vented Barrel

Cartridge

Wt (gr.)

Stylea

(ft/sec)

(ft/sec)

.38 Special

125

SJHP

1028

945

148

WC

770

710

158

Lead RN

885

755

200

Lead RN

730

635

.357 Magnum

125

SJHP

1675

1450

158

SJHP

1550

1235

158

Lead SWC

1410

1235

a SJHP = semi-jacketed hollow-point; WC = wadcutter; RN = roundnose; SWC = semiwadcutter.

a SJHP = semi-jacketed hollow-point; WC = wadcutter; RN = roundnose; SWC = semiwadcutter.

differences in the Saturday night specials. Experiments, however, do not always substantiate this. The results of one such test can be seen in Table 5.3. There are no significant differences between the muzzle velocities of the Saturday night specials and those of well-made Smith & Wesson revolvers.

Handgun wounds can be divided into four categories, depending on the distance from muzzle to target. These are: contact, near contact, intermediate, and distant (see Chapter 4).

Table 5.3 Muzzle Velocities of .38 Special Cartridges Fired in Smith and Wesson and "Saturday Night Special" Revolvers of Various Barrel Lengths

Barrel Length

Muzzle Velocity (ft/sec ± 1 S.D.)

Smith & Wesson

R.G.

2 in.

687 ± 8

677 ± 11

4 in.

687 ± 15

722 ± 31

6 in.

765 ± 13

748 ± 18

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