Advanced 140-mm Tank Gun

Today, the vast majority of modern models of the world are used smoothbore tank 120, and 125-mm guns . The exceptions are India's Arjun and British Challenger I and II, which are equipped with a rifled 120-mm guns. The transition in the second half of XX century on the smooth-bore guns will significantly increase the kinetic energy of the projectile, thereby improving the armor.


• In this free miracles, as we know, does not happen, and the smooth-bore guns are inferior to the rifle range and accuracy of aimed fire . These features and give rise to the application of modern tank fire control complex systems.


• In the near future, increasing the firepower of the tanks will be due both to improve the artillery, and increase the power of ammunition. The increase in the caliber of tank guns is not a prerequisite. Improved design tools is on the way to improve the quality of steel, which is used for the manufacture of the barrel in order to increase the gas pressure in the chamber and the barrel when fired. And also on the way to reduce uneven heating, backlash, moments and other phenomena affecting the trunk and on the accuracy.


• In the future you can expect an increase in firepower MBT and through the use of larger caliber guns. Currently, the Swiss company RUAG armourers of the established tank smoothbore gun, 140 mm . Features of the new gun is not fully known, but there is information about what worked for RUAG option to install this tool in the fighting compartment of the tank Leopard 2A4. His research in this area are conducted in the United States, where an instrument is developed smooth dvukalibernoe XM291 120/140 mm. Leads the development in this direction, and Ukraine, where the instrument was set up 55L "Bagheera".

•  In Russia, most experts agree on the notion to leave as the main tank gun caliber artillery systems from 125 mm , but with an increased length of the barrel and the ability to use armor-piercing projectiles with increased length of armor-piercing core. It has also been created and passed the test of larger caliber smoothbore gun.


• It should be understood that the increase in the caliber of tank guns to 140 mm leads to almost halve the transported ammunition inside the tank . That is what today is the main limiting factor for use in large-caliber tank guns.


German 140-mm smoothbore gun company "Rheinmetall"


• Under contract with the federal management of supply of arms (VWV), the German company "Rheinmetall" produced six prototypes of the 140-mm smoothbore guns and ammunition series of APFSDS-T (armor-piercing tracer feathered fly off with the leading parts) for testing.


• The development was conducted in an international program to create the main armament for a tank of the future FTMA, which is implemented by Britain, France, Germany and the United States. new 140-mm gun received the designation NPz K-140 . This instrument is equipped with a heat-insulating cover, wedge bolt vertically incident type, gunpowder smoke extractor. The gun was designed to increase the firepower of the German main battle tank "Leopard 2" .

• It is assumed that the installation of the tank 140-mm guns require replacement of the tower, which would get the automatic loader for separate loading 140mm ammunition. Made a test stand, but not in production or in service with this gun yet.


Swiss 140-mm tank gun


• Work on the creation of a new 140-mm tank gun began in Switzerland in the late 1980s of the XX century. The firm "Ordnance Enterprise" has launched a program that was intended to demonstrate the ability to use a more powerful guns not only to modernize the standing armed with tanks "Leopard 2", but also as a fortress gun. Also, a new tool to be used to integrate it, and new weapons available in the MBT with minimal cost and to verify the expected performance of new ammunition.


•  The first ballistic testing of a new 140-mm smoothbore gun in a real combat situation took place in the summer of 1988 and the first firing ammunition from a gun mounted on the tank "Leopard 2" , held in autumn 1989 . Towards a new gun has been created separate loading ammunition, consisting of the main propellant charge, which is a steel base and combustible container (approximately 10 kg warhead) and the projectile kinetic action, plus an additional 5 kg warhead. It also created a multi-purpose missile (MR), which probably will not require any additional charge.


• Kinetic projectiles have an elongated core, which is made of base metal, and not from depleted uranium, which is applied in the U.S. Munitions and body with a plastic driving bands. At the same time, the first multi-shot is a shaped-charge projectile having an additional rather strong fragmentation effect.

• Swiss chamber 140-mm gun is somewhat shorter than the arrangement adopted by NATO countries, while according to the "Ordnance Enterprise," this gun and ammunition to it if necessary can be quickly adjusted to the existing international standards on the chamber.


• The main efforts of Swiss engineers to create new weapons based on the analysis of external ballistics on the final trajectory of the kinetic ammunition, with different structural characteristics (diameter, weight, length, speed) tested against a number of purposes. In parallel, the effects of multi-shells was investigated in static tests.


• It should be noted that Swiss 140-mm smoothbore gun is still only a test gun . And given the significant reduction in the threat of war in Europe since the beginning of its development in the foreseeable future, it will not be put into operation.

Development of 140-mm guns in the UK


• Over the years, the former UK Ministry of Defence R & D Management (DRA) employed on the project a 140-mm tank gun for the future of FTMA. Initially it was planned that created an instrument will be ready for production in the army at the beginning of the XXI century, but the collapse of the USSR and the demise of the Warsaw Pact significantly slowed work on the program, and the cannon had been received in industrial production.


•  In the UK implemented two programs : one funded by the Ministry of Defense and manage DRA, the major work on it were made ​​from 1989 to 1992. The second program was initiated by "Royal Ordnance" and ran from 1989 to 1993.

• By early 1993, "Royal Ordnance" and DRA had a fire out of their 140-mm shells at the sites of the country. The company "Royal Ordnance" had about 120 rounds ammunition APFSDS from its 140-mm gun mounted on a test bench. This gun is provided a 40% increase in armor penetration compared with the 120-mm guns . 140-mm ammunition for the new instruments were significantly heavier than the existing 120-mm shells, and therefore made ​​separate, consisting of two parts (projectile and charge), who were charged into a tool with automatic loader.


• As it turned out, the installation of a new 140-mm gun with automatic loader on the tanks , "Challenger 2" or M-1A1/A2 Abrams was very expensive. In the new French tank "Leclerc" in the niche of the tower was installed automatic loader, but the main gun of the tank left the 120-mm gun. It was assumed that the shells APFSDS, which were used in the tank of the future FTMA, will have a core of depleted uranium. These munitions have better armor penetration, but at the same time have high production costs and can not be used in peacetime for environmental reasons.

140-mm gun is a promising system ATAC U.S.


• In the U.S. system is a promising smoothbore tank gun caliber 140-mm (ATAS) is a cannon XM-291 XM-automatic loader 91 and a family of new ammunition. It was assumed that the system will become the main weapon of the future MBT project "Block III», which is being developed for the U.S. Army.


• 140-mm gun XM-291 is a powder-tank gun with a monolithic installation and rollback mechanism, which is firing ammunition, consisting of 2 parts (projectile and charge). Muzzle energy of the gun 2 times the energy of a standard 120-mm gun M-256, which are armed with tanks , "Abrams' M1A2 . The gun has an extractor powder smoke, heat-insulating cover and 91 pounds lighter than the standard M-256 guns.



•  The uniqueness of the developed system is that after replacing the barrel (it takes about an hour), the system can fire a 120 mm solid conventional and advanced ammunition . The gun works in conjunction with the automatic loader XM-91, which is able to recognize the selected type of munition. The mechanism of transfer of ammunition was created by "Lockheed Martin".

• In the niche of turret contains 17 pieces of 120 mm or 140-mm rounds, ready for immediate use, another 22 140-mm round in two parts, or 33 caliber ammunition unitary 120 mm can be placed in the hull of the tank. Using the autoloader allows for the rate of fire at 8-12 rounds per minute.


•  The family of ammunition for the ATAS system is represented by three rounds : the cumulative XM-965 projectile, projectile kinetic of the XM-964 projectile and educational XM-966 . Every shot is composed of a charge and a projectile. The charge is identical for all three rounds and consists of a block of the detonator and the base of the truncated part, combustible side wall of ignition and propellant charge. When fired, the shell burns, leaving behind only the base. Snap connection with the projectile charge allows you to remove the projectile from the breech of the barrel.


• The prototypes developed by ATAC system is tested in the U.S. Army Forces, while on an industrial scale 140-mm tank gun perspective is not performed.

Ukrainian 140-mm gun, "Bagheera"


• In Ukraine, as were the development of instruments of caliber 140 mm. As a result of construction work came to light L55 gun, "Bagheera", number 55 in the name indicates the length of the barrel in calibers. This gun is designed for upgrading existing weapons, and advanced models of armored vehicles. An option for installing it on the T-84M "Hold", but realized he was not.



Characteristics of the experimental tank gun L55 "Bagheera," : 
caliber - 140 mm 
Barrel length - 7000 mm (55 gauge) 
Maximum length of a rollback - 310 mm 
Muzzle velocity - 1870 m / s 
Kreshernoe pressure - 564 MPa 
Muzzle energy - 15.74 MJ 
Receiver weight BPS - 9 kg 
BPS Flight weight - 7 lbs.