2A28 Grom
Encyclopedia
The 2A28 Grom is the main armament of the BMP-1
infantry fighting vehicle
. It is a 73 mm low pressure smoothbore
semi-automatic gun with wedge breechblock.
is between 8 and 10 rounds per minute, with the gun returning to an elevation of +3° 30' to reload after each shot if the autoloader is used.
It is fed from a forty round mechanized conveyor double-row magazine located around the turret ring of the BMP. The gun is reloaded by the M3 electromechanical autoloader
with ammunition conveyor, but can be reloaded by hand if necessary. The autoloader is not reliable; it can break down from vibration when the vehicle is moving at high speed over rough ground, and its operation is a danger to the gunner's fingers. Using the autoloader, the gun has a rate of fire of 6–8 rounds per minute while a skilled gunner could easily achieve 10 rounds per minute. These drawbacks caused the autoloader to be removed in Ob'yekt 765Sp3 and Finnish BMP-1. Some units removed the autoloader altogether when new vehicles were delivered, but the mechanized ammunition conveyor magazine was kept.
infantry light recoilless gun but with a smaller propellant charge. Before 1974 the ammunition consisted of high explosive anti-tank (HEAT
) rounds only; the PG-15V HEAT fixed fin-stabilized rocket-assisted round. After 1974, OG-15V HE-Fragmentation projectiles were introduced. In the Ob'yekt 765Sp3, the standard ammunition load is 24 PG-15V HEAT rounds and 16 OG-15V HE-Frag rounds.
The PG-15V HEAT round weighs 3.47 kilogram and uses a 2.6 kilogram PG-9 shell with a 0.322 kilogram RDX
explosive charge in the warhead. A small PG-15P powder charge is used to boost the projectile from the gun barrel at 400 m/s. Once the projectile has travelled 10 –, the rocket motor starts and accelerates it to 700 m/s. If this low speed projectile's fins catch a crosswind it tends to "shuttlecock" with a consequent reduction in accuracy.
The OG-15V HE-Frag round weighs 4.57 kilogram, it uses a OG-9 shell with a 0.73 kilogram TNT bursting charge. The muzzle velocity of the OG-9 is 290 m/s. The OG-15V is loaded by hand as it is too short to be handled by the autoloader.
, the British Chieftain
or the German Leopard 1. The modernised PG-9 shell is able to penetrate up to 400 millimetres (15.7 in) of steel armor. The BMP-1's gun is unable to penetrate the front armor of modern NATO MBTs such as the US M1A1 Abrams
, the British Challenger 2
or the German Leopard 2
but it has been claimed that it can penetrate the side armor of these tanks in some areas.
On the ranges the PG-9 proved capable of hitting a 2 metres (6.6 ft) high target at a range of 765 metres (836.6 yd), while its maximum direct fire range is 1300 metres (1,421.7 yd), reduced to 400 metres (437.4 yd) at night, due to the limitations of the night vision system. Under battlefield conditions it has a maximum effective range of 500 metres (546.8 yd).
Maximum effective indirect range of the OG-15V HE-Frag round against formation targets is 4400 metres (4,811.9 yd). Its effective direct fire range against small point targets is around 1000 metres (1,093.6 yd).
A coaxial 7.62 mm PKT machine gun is mounted to the right of the main armament for which the BMP-1 carries 2,000 rounds in belts of 250. They are stowed in two boxes under the main gun. The machine gun has a rate of fire of around 200–250 rounds a minute.
The 2A28 "Grom" gun and PKT coaxial machine gun cannot be accurately fired while the vehicle moving over rough ground. This means that the BMP-1's main armament less capable than modern stabilised autocannons which can be fired accurately while moving. The BMP-1 is unable to engage tanks and APCs using the 2A28 "Grom" gun from hull-down positions due to its limited depression, making it vulnerable to enemy fire. The limited elevation of the main gun, its lack of firepower and inaccuracy against point targets at 500–700 m (546.8–765.5 yd) meant that it could not fight effectively in the mountains of Afghanistan.
The BMP-1 was a threat to NATO APCs, light AFVs and even MBTs, from the PG-15V shell at short range, and the 9M14M Malyutka-M anti-tank guided missile
(ATGM) at longer ranges.
BMP-1
The BMP-1 is a Soviet amphibious tracked infantry fighting vehicle. BMP stands for Boyevaya Mashina Pekhoty 1 , meaning "infantry fighting vehicle". The BMP-1 was the world's first mass-produced infantry fighting vehicle...
infantry fighting vehicle
Infantry fighting vehicle
An infantry fighting vehicle , also known as a mechanized infantry combat vehicle , is a type of armoured fighting vehicle used to carry infantry into battle and provide fire support for them...
. It is a 73 mm low pressure smoothbore
Smoothbore
A smoothbore weapon is one which has a barrel without rifling. Smoothbores range from handheld firearms to powerful tank guns and large artillery mortars.-History of firearms and rifling:...
semi-automatic gun with wedge breechblock.
Description
The gun is relatively compact and weighs 115 kilograms (253.5 lb). In the BMP, the gun is brought to bear by electric motor, with a manual mechanical backup. The maximum horizontal and vertical traverse speed with the electrical system is 20 °/s and 6 °/s respectively. Minimum horizontal and vertical direction rate is correspondingly 0.1 °/s and 0.07 °/s. The gun can be depressed and elevated between −4° and +33°, with aimed fire possible up to an elevation of +15°. The turret can traverse 360°. Cyclic rate of fireRate of fire
Rate of fire is the frequency at which a specific weapon can fire or launch its projectiles. It is usually measured in rounds per minute , or per second .-Overview:...
is between 8 and 10 rounds per minute, with the gun returning to an elevation of +3° 30' to reload after each shot if the autoloader is used.
It is fed from a forty round mechanized conveyor double-row magazine located around the turret ring of the BMP. The gun is reloaded by the M3 electromechanical autoloader
Autoloader
An autoloader or auto-loader is a mechanical aid or replacement for the personnel that load ordnance into crew-served weapons, such as tanks and artillery...
with ammunition conveyor, but can be reloaded by hand if necessary. The autoloader is not reliable; it can break down from vibration when the vehicle is moving at high speed over rough ground, and its operation is a danger to the gunner's fingers. Using the autoloader, the gun has a rate of fire of 6–8 rounds per minute while a skilled gunner could easily achieve 10 rounds per minute. These drawbacks caused the autoloader to be removed in Ob'yekt 765Sp3 and Finnish BMP-1. Some units removed the autoloader altogether when new vehicles were delivered, but the mechanized ammunition conveyor magazine was kept.
Ammunition
The 2A28 'Grom' smoothbore gun fires the same projectiles as the SPG-9SPG-9
The SPG-9 Kopye is a Russian tripod-mounted man-portable, 73 millimetre calibre recoilless gun developed by the Soviet Union. It fires fin-stabilised, rocket-assisted HE and HEAT projectiles similar to those fired by the 73 mm 2A28 Grom low pressure gun of the BMP-1 vehicle...
infantry light recoilless gun but with a smaller propellant charge. Before 1974 the ammunition consisted of high explosive anti-tank (HEAT
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...
) rounds only; the PG-15V HEAT fixed fin-stabilized rocket-assisted round. After 1974, OG-15V HE-Fragmentation projectiles were introduced. In the Ob'yekt 765Sp3, the standard ammunition load is 24 PG-15V HEAT rounds and 16 OG-15V HE-Frag rounds.
The PG-15V HEAT round weighs 3.47 kilogram and uses a 2.6 kilogram PG-9 shell with a 0.322 kilogram RDX
RDX
RDX, an initialism for Research Department Explosive, is an explosive nitroamine widely used in military and industrial applications. It was developed as an explosive which was more powerful than TNT, and it saw wide use in WWII. RDX is also known as cyclonite, hexogen , and T4...
explosive charge in the warhead. A small PG-15P powder charge is used to boost the projectile from the gun barrel at 400 m/s. Once the projectile has travelled 10 –, the rocket motor starts and accelerates it to 700 m/s. If this low speed projectile's fins catch a crosswind it tends to "shuttlecock" with a consequent reduction in accuracy.
The OG-15V HE-Frag round weighs 4.57 kilogram, it uses a OG-9 shell with a 0.73 kilogram TNT bursting charge. The muzzle velocity of the OG-9 is 290 m/s. The OG-15V is loaded by hand as it is too short to be handled by the autoloader.
Performance
The HEAT warhead can penetrate 280 – of steel armor—more than enough to penetrate the frontal armor of NATO main battle tanks (MBT)s of the 1970s, such as the US M60A1M60 Patton
The 105 mm Gun Full Tracked Combat Tank, M60, also known unofficially as the M60 Patton, is a first-generation main battle tank introduced in December 1960. It was widely used by the U.S. and its Cold War allies, especially those in NATO, and remains in service throughout the world today...
, the British Chieftain
Chieftain tank
The FV 4201 Chieftain was the main battle tank of the United Kingdom during the 1960s and 1970s. It was one of the most advanced tanks of its era, and at the time of its introduction in 1966 had the most powerful main gun and heaviest armour of any tank in the world...
or the German Leopard 1. The modernised PG-9 shell is able to penetrate up to 400 millimetres (15.7 in) of steel armor. The BMP-1's gun is unable to penetrate the front armor of modern NATO MBTs such as the US M1A1 Abrams
M1 Abrams
The M1 Abrams is a third-generation main battle tank produced in the United States. It is named after General Creighton Abrams, former Army Chief of Staff and Commander of US military forces in Vietnam from 1968 to 1972. The M1 is a well armed, heavily armored, and highly mobile tank designed for...
, the British Challenger 2
Challenger 2 tank
FV4034 Challenger 2 is a British main battle tank currently in service with the armies of the United Kingdom and Oman. It was designed and built by the British company Vickers Defence Systems . The manufacturer advertises it as the world's most reliable main battle tank...
or the German Leopard 2
Leopard 2
The Leopard 2 is a main battle tank developed by Krauss-Maffei in the early 1970s for the West German Army. The tank first entered service in 1979 and succeeded the earlier Leopard 1 as the main battle tank of the German Army. Various versions have served in the armed forces of Germany and twelve...
but it has been claimed that it can penetrate the side armor of these tanks in some areas.
On the ranges the PG-9 proved capable of hitting a 2 metres (6.6 ft) high target at a range of 765 metres (836.6 yd), while its maximum direct fire range is 1300 metres (1,421.7 yd), reduced to 400 metres (437.4 yd) at night, due to the limitations of the night vision system. Under battlefield conditions it has a maximum effective range of 500 metres (546.8 yd).
Maximum effective indirect range of the OG-15V HE-Frag round against formation targets is 4400 metres (4,811.9 yd). Its effective direct fire range against small point targets is around 1000 metres (1,093.6 yd).
The 2A28 "Grom" gun and PKT coaxial machine gun cannot be accurately fired while the vehicle moving over rough ground. This means that the BMP-1's main armament less capable than modern stabilised autocannons which can be fired accurately while moving. The BMP-1 is unable to engage tanks and APCs using the 2A28 "Grom" gun from hull-down positions due to its limited depression, making it vulnerable to enemy fire. The limited elevation of the main gun, its lack of firepower and inaccuracy against point targets at 500–700 m (546.8–765.5 yd) meant that it could not fight effectively in the mountains of Afghanistan.
The BMP-1 was a threat to NATO APCs, light AFVs and even MBTs, from the PG-15V shell at short range, and the 9M14M Malyutka-M anti-tank guided missile
Anti-tank guided missile
An anti-tank missile , anti-tank guided missile , anti-tank guided weapon or anti-armor guided weapon is a guided missile primarily designed to hit and destroy heavily-armored military vehicles....
(ATGM) at longer ranges.
See also
- M242 BushmasterM242 BushmasterThe M242 Bushmaster is a 25 mm chain-fed autocannon. It is used extensively by the US armed forces, as well as by NATO's and some other nations' forces in ground combat vehicles and watercraft...
- 9M113 Konkurs
- BMP DevelopmentBMP DevelopmentThe BMP series of infantry fighting vehicles were the first production line IFVs. Included in the series are the mainline BMPs, the airborne variant BMDs, and licensed modified and reverse engineered versions . BMP stands for Boyevaya Mashina Pekhoty , meaning "fighting vehicle of infantry")...
- BMP-1BMP-1The BMP-1 is a Soviet amphibious tracked infantry fighting vehicle. BMP stands for Boyevaya Mashina Pekhoty 1 , meaning "infantry fighting vehicle". The BMP-1 was the world's first mass-produced infantry fighting vehicle...
- BMD-1BMD-1The BMD-1 is a Soviet airborne amphibious tracked infantry fighting vehicle, which was introduced in 1969 and first seen by the West in 1970. BMD stands for Boyevaya Mashina Desanta . It can be dropped by parachute and although it resembles the BMP-1 it is in fact much smaller...
- SPG-9SPG-9The SPG-9 Kopye is a Russian tripod-mounted man-portable, 73 millimetre calibre recoilless gun developed by the Soviet Union. It fires fin-stabilised, rocket-assisted HE and HEAT projectiles similar to those fired by the 73 mm 2A28 Grom low pressure gun of the BMP-1 vehicle...