M7 grenade launcher
Encyclopedia
The M7 grenade launcher, formally Rifle Grenade Launcher, M7 was a 22 mm
rifle grenade
launcher attachment for the M1 Garand
rifle which saw widespread use throughout World War II
and the Korean War
. The M7 was a tube-shaped device, one end that slotting over the barrel of the rifle, the other end holding the grenade in place. Blank cartridges
were loaded into the rifle prior to firing. When fired, the expanding gases generated by the cartridges propelled the grenade forward with considerable force. The M7 could fire grenades up to 350 metres (375 yards), compared the maximum of 30 metres (35 yards) achieved by hand grenades.
Fragmentation, anti-armour and smoke grenades were available for the M7.
fragmentation hand grenade
. Owing to its hand-thrown nature it had limited range of 35 yards (about 32 meters) and could not be used against armored targets. To keep its weight down it had to have a small charge, with a fatality radius of just 6 yards (5.5 meters). For longer ranges rifle grenade attachments were available for the M1903 Springfield and M1917 Enfield, though these rifles were rare as they had been all but replaced by the M1 Garand by 1943. To rectify this, U.S. Army Ordnance designed a new launcher attachment for the M1 Garand, designated the M7, which could fire much heavier grenades up to 330 yards (301.75 meters). M7 compatible fragmentation grenades had a fatality radius of 11 yards (10 meters). It entered production and service in 1943.
. The other end was cylindrical with a small clip that held the grenade in place by friction. To launch a grenade, a special high powered blank cartridge (M3 .30-'06) made specifically for the purpose was inserted into the rifle. Using markings engraved onto the device to determine the desired range, the rifle grenade was slipped over the launcher and held in place by the clip. When fired, the resulting expanding gases propelled the grenade a considerable distance depending on the grenade type, the vertical angle that the rifle was held, and how far the grenade was positioned onto the launcher. Since the device disabled the semi-automatic
function of the rifle to prevent damage to the gun from firing grenades, the rifle could not be fired normally when the M7 launcher was in place, although, the gun could be fired in an emergency as a single action. Fragmentation, anti-armor and smoke grenades were available along with an adapter to enable the use of hand grenades. Three M7 grenade launchers were issued to each rifle squad.
The M8 grenade launcher was similar except it was designed to be mounted on the M1 Carbine
and used the M6 .30 Carbine
blank. The recoil could crack or break the stock
22 mm grenade
The 22mm rifle grenade is inserted over the firing mechanism on the front of rifles that are equipped with the appropriate launcher, either in the form of an integral flash suppressor or a detachable adapter. As with most rifle grenades, it is propelled by a blank cartridge inserted into the...
rifle grenade
Rifle grenade
A rifle grenade is a grenade that uses a rifle-based launcher to permit a longer effective range than would be possible if the grenade was thrown by hand...
launcher attachment for the M1 Garand
M1 Garand
The M1 Garand , was the first semi-automatic rifle to be generally issued to the infantry of any nation. Called "the greatest battle implement ever devised" by General George S...
rifle which saw widespread use throughout World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
and the Korean War
Korean War
The Korean War was a conventional war between South Korea, supported by the United Nations, and North Korea, supported by the People's Republic of China , with military material aid from the Soviet Union...
. The M7 was a tube-shaped device, one end that slotting over the barrel of the rifle, the other end holding the grenade in place. Blank cartridges
Blank (cartridge)
A blank is a type of cartridge for a firearm that contains gunpowder but no bullet or shot. When fired, the blank makes a flash and an explosive sound . Blanks are often used for simulation , training, and for signaling...
were loaded into the rifle prior to firing. When fired, the expanding gases generated by the cartridges propelled the grenade forward with considerable force. The M7 could fire grenades up to 350 metres (375 yards), compared the maximum of 30 metres (35 yards) achieved by hand grenades.
Fragmentation, anti-armour and smoke grenades were available for the M7.
Development
When the United States entered World War II in 1941, all infantry were issued with the Mk 2Mk 2 grenade
The Mk 2 defensive hand grenade is a fragmentation hand grenade used by the U.S. armed forces during World War II and in later conflicts including the Vietnam War. The Mk II was standardized in 1920 replacing the Mk I of 1917. It was phased out gradually, the U.S. Navy being the last users...
fragmentation hand grenade
Hand grenade
A hand grenade is any small bomb that can be thrown by hand. Hand grenades are classified into three categories, explosive grenades, chemical and gas grenades. Explosive grenades are the most commonly used in modern warfare, and are designed to detonate after impact or after a set amount of time...
. Owing to its hand-thrown nature it had limited range of 35 yards (about 32 meters) and could not be used against armored targets. To keep its weight down it had to have a small charge, with a fatality radius of just 6 yards (5.5 meters). For longer ranges rifle grenade attachments were available for the M1903 Springfield and M1917 Enfield, though these rifles were rare as they had been all but replaced by the M1 Garand by 1943. To rectify this, U.S. Army Ordnance designed a new launcher attachment for the M1 Garand, designated the M7, which could fire much heavier grenades up to 330 yards (301.75 meters). M7 compatible fragmentation grenades had a fatality radius of 11 yards (10 meters). It entered production and service in 1943.
Design details and employment
The M7 grenade launcher was a tube shaped device. One end fitted onto the barrel of the M1 Garand rifle enclosing the muzzle and was held in place with the rifle's bayonet lugBayonet lug
A bayonet lug is a standard feature on most military muskets, rifles, and shotguns, and on some civilian longarms. It is intended for attaching a bayonet, which is typically a long spike or thrusting knife...
. The other end was cylindrical with a small clip that held the grenade in place by friction. To launch a grenade, a special high powered blank cartridge (M3 .30-'06) made specifically for the purpose was inserted into the rifle. Using markings engraved onto the device to determine the desired range, the rifle grenade was slipped over the launcher and held in place by the clip. When fired, the resulting expanding gases propelled the grenade a considerable distance depending on the grenade type, the vertical angle that the rifle was held, and how far the grenade was positioned onto the launcher. Since the device disabled the semi-automatic
Semi-automatic firearm
A semi-automatic, or self-loading firearm is a weapon which performs all steps necessary to prepare the weapon to fire again after firing—assuming cartridges remain in the weapon's feed device or magazine...
function of the rifle to prevent damage to the gun from firing grenades, the rifle could not be fired normally when the M7 launcher was in place, although, the gun could be fired in an emergency as a single action. Fragmentation, anti-armor and smoke grenades were available along with an adapter to enable the use of hand grenades. Three M7 grenade launchers were issued to each rifle squad.
The M8 grenade launcher was similar except it was designed to be mounted on the M1 Carbine
M1 Carbine
The M1 carbine is a lightweight, easy to use semi-automatic carbine that became a standard firearm for the U.S. military during World War II, the Korean War and the Vietnam War, and was produced in several variants. It was widely used by U.S...
and used the M6 .30 Carbine
.30 Carbine
The .30 Carbine is the cartridge used in the M1 Carbine introduced in the 1940s. It is an intermediate round designed to be fired from the M1 carbine's 18-inch barrel.-History:...
blank. The recoil could crack or break the stock
Improved Models
- M7A1 (Springfield Armory T95) [July, 1945 - 1951]: The major problem with the M7 grenade launcher is that it left the gas cylinder lock closed when attached, venting the cylinder. This meant the operator would have to cock the weapon to extract the spent cartridge and load a fresh one from the en-bloc clip in the magazine. The M7A1 incorporated a spring-loaded piston designed to keep the gas cylinder closed when loaded until the grenade was fired, but then opened to allow normal semi-automatic function. The spring-loaded launcher also recoiled when fired, preventing damage to the rifle. The M1 Garand design was modified to use a hardened gas cylinder lock (marked with an 'H', for "Hardened") dubbed the "Flat-Edged Lock" (Ordnance Part No. 7265959). This allowed prolonged use of the new launcher system.
- M7A2 [July, 1951]: The only problem with the M7A1 was that sometimes the launcher would get stuck when fired or the gas cylinder lock would break. This rendered the rifle and launcher useless and required repair by an armorer with special tools. The jamming problem was solved by using a heavier spring-loaded piston on the launcher and introduced a redesigned grenade retaining spring. The M1 Garand was then modified with a distinctive dual gas cylinder lock (marked with a 'M', for "Modified") dubbed the "High Hump Lock" (Ordnance Part No. 7265871). The launcher had a mount machined into it to take a proposed leaf-sight that was never adopted.
- M7A3 (Ordnance Part Number 7266167) [September, 1952]: During the Korean WarKorean WarThe Korean War was a conventional war between South Korea, supported by the United Nations, and North Korea, supported by the People's Republic of China , with military material aid from the Soviet Union...
, it was found that the World War IIWorld War IIWorld War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
-era Anti-Tank grenades were useless against the Soviet T-34T-34The T-34 was a Soviet medium tank produced from 1940 to 1958. Although its armour and armament were surpassed by later tanks of the era, it has been often credited as the most effective, efficient and influential design of World War II...
tanks fielded by the North Korean army. A new high-velocity anti-tank rifle grenade called the Mecar ENERGAENERGA anti-tank rifle grenadeThe Energa anti-tank rifle grenade is a rifle-launched anti-tank grenade that is propelled by a ballistite-filled blank cartridge. The name Energa comes from the firm in Liechtenstein that designed it, the Anstalt für die ENtwicklung von ERfindungen und Gewerblichen Anwendungen, based in...
(dubbed the M28 in US Army service) was soon issued. However, its grenade launcher (dubbed the T119) had the same problems as the original M7 launcher and the M28 was inaccurate when launched from the M7A2. The M7A2 launcher was simply redesigned with a longer tube to fire the improved grenades and could be used with either the "Flat Edge" or "High Hump" lock. After the war (from early 1956 to late 1959) it could be fitted with a leaf-sight that was calibrated for use with the M28. The M7A3 Kit (Ordnance Part No. 5750089) consisted of a M7A3 launcher packed with a "High Hump" gas lock to allow the grenadier to upgrade an earlier model M1 Garand to the new specification.