.30 Carbine

.30 Carbine (7.62×33mm)

Type

Carbine

Place of origin

United States

Service history

In service

World War II–present

Used by

See Users

Wars

World War II
Korean War
Vietnam War

Production history

Produced

World War II to 1950s, present (civilian)

Variants

M1 (Ball),
M6 (Grenade),
M13 (Dummy),
M18 (Heavy, High Pressure Test) 152gr,
M27 (Tracer)

Specifications

Parent case

.32 Winchester Self-Loading

Bullet diameter

7.62 mm (nominal, 0.308 in actual)

Neck diameter

8.41 mm (0.331 in)

Base diameter

8.99 mm (0.354 in)

Rim diameter

9.14 mm (0.360 in)

Rim thickness

1.27 mm (0.050 in)

Case length

32.76 mm (1.290 in)

Overall length

41.91 mm (1.650 in)

Case capacity

1.3640 cm³ (21.050 gr H₂O)

Rifling twist

1:20"

Primer type

Small rifle

Maximum pressure

265.45 MPa (38,500 psi)

Ballistic performance

Bullet mass/type	Velocity	Energy
110 gr (7 g) FMJ	606.5 m/s (1,990 ft/s)	1,311 J (967 ft·lbf)

Test barrel length: 18 inches
Source(s): Winchester

The .30 Carbine (7.62×33mm) is the cartridge used in the M1 Carbine introduced in the 1940s. It is a light rifle round designed to be fired from the M1 carbine's 18-inch (458 mm) barrel.

Shortly before World War II, the U.S. Army started a "light rifle" project to provide support personnel and rear area units more firepower and accuracy than the standard issue M1911A1 .45 ACP caliber handgun at half the weight of the M1 Garand rifle or the .45 Thompson submachine gun. The .30 Carbine cartridge was developed by Winchester and is basically a rimless .30 caliber (7.62 mm) version of the much older .32 Winchester Self-Loading cartridge of 1906 introduced for the Winchester Model 1905 rifle. The propellant was much newer, though, taking advantage of chemistry advances. As a result, the .30 Carbine is approximately 27% more powerful than its parent cartridge. The .30 Carbine's relatively straight case and the rounded nose of its bullet led some to believe it was designed for use in pistols.

At first, Winchester was tasked with developing the cartridge but did not submit a carbine design. Other firms and individual designers submitted several carbine designs, but most prototypes were either unreliable or grossly off the target weight of five pounds. Maj. Rene Studler persuaded Winchester that the Winchester M2 .30-06 rifle, a design started by Ed Browning and perfected by Winchester engineer Marshall Williams, could be scaled down for the .30 Carbine cartridge.

The M1 Carbine was issued to infantry officers, machine gun, artillery and tank crews, paratroopers and other line-of-communications personnel in lieu of the larger, heavier M1 Garand. The weapon was originally issued with a 15-round detachable magazine. The Carbine and cartridge were not intended to serve as a primary infantry weapon, nor was it comparable to more powerful intermediate cartridges later developed for assault rifles. The M2 Carbine was introduced late in World War II with a selective-fire switch allowing optional fully automatic fire at a rather high rate (850–900 rpm) and a 30-round magazine.

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Wikipedia