Now the vast majority of contemporary models of tanks worldwide and smooth-120 and 125-mm guns. The exceptions are Indian Arjun and British Challenger I and II, which are equipped with 120-mm rifled guns. Going into the second half of the XX century smoothbore gun has permitted significant increment the kinetic energy of the projectile, the improved armor. With all this free of miracles, as we know, does not happen, and rifled guns of inferior in accuracy and range of aimed fire. These features and give rise to the application of modern tanks sophisticated fire control systems.In the recent increase in the firepower of tanks is due both to the improvement of artillery, and increase the power of weapons. With all of this increase in the caliber of tank guns is not a condition of mandatory. Improving the design of tools is on the way to improve the properties of steel, which is used for the production of the barrel, in order to increase the gas pressure in the breech and the barrel when fired. Also on ways to reduce the uneven heating backlash, moments, and other phenomena affecting the trunk and accuracy. In the future, you can expect an increase in the firepower of the MBT and through the introduction of large-caliber guns. At the current time the Swiss gunsmiths of the company RUAG created smoothbore tank gun, 140-mm. Properties of the new instrument is not fully known, but there is information about what has worked RUAG option to install this tool in fighting compartment of the tank Leopard 2A4. The development in this area are in progress in the United States, where developed smooth dvukalibernoe gun XM291 120/140 mm. Leads the development in this direction, and Ukraine, where the instrument was created 55L «Bagheera».
Tank gun 2A75 (left) and 2A46M-5 (right). 2A46M-5 — the most modern Russian tank gun, 125-mm
In Russia, most experts agree that the outlook to cast as the main tank gun artillery system caliber 125 mm, but with the increased length of the barrel and the possibility of the introduction of armor-piercing projectiles with increased length of the armor-piercing core. It was also created and passed the test of greater caliber smoothbore gun. With all of this it is worth understanding that the increase in the caliber of tank guns to 140 mm leads to virtually halve transported inside the tank ammunition. Specifically, it is currently the main constraint on the use of tanks in large-caliber guns. German 140-mm smoothbore gun of «Rheinmetall» Under an agreement with the Federal Office supplies of weapons (VWV) German company «Rheinmetall» made 6 of prototypes 140-mm smoothbore guns and ammunition series of APFSDS-T (armor-piercing tracer feathered with separable leading parts) for testing. This development was carried out in the framework of international programs from the creation of the main armament of the tank for the future FTMA, which is implemented by the United Kingdom, France, Germany and the United States. The new 140-mm gun received the designation NPz K-140. This instrument is equipped with a heat insulating cover, breech vertically incident type extractor gunpowder. The gun was designed to increase the firepower of Germany’s main battle tank «Leopard 2». With all of this means that the installation of the tank on a 140-mm gun turret reclaims substitution, which would get the automatic loader for separate loading 140-mm ammunition. Made a test board, but not in production or in the arms of this gun, as it were still there.
Tank guns produced by «Rheinmetall» 120 mm with a barrel of 44 and 55 gauge and 140-mm gun NPz K-140
Swiss 140-mm tank gun Work on the creation of the newest 140-mm tank gun began in Switzerland in the late 1980-ies of XX century. The company «Ordnance Enterprise» has launched a program that was intended to demonstrate the ability to use more powerful guns not only to modernize the standing armed tanks «Leopard 2», and as a fortress gun. Also, a new tool to be used to its integration and new ammunition available in the MBT at the lowest cost and to verify the expected features of the new ammunition. First ballistic testing the newest 140-mm smoothbore gun in the criteria of a real combat situation took place in the summer of 1988, and the first firing ammunition from a gun mounted on a tank «Leopard 2», was accomplished in the autumn of 1989. For the latest gun was made of separate loading ammunition, consisting of a main propellant, is a iron base and a combustible container (approximately 10 kg. Warhead) and the projectile kinetic acts plus an extra 5 kg. warhead. Also created was a multi-purpose missile (MR), which is not likely to use will claim an additional charge. The kinetic projectiles possess an elongated core, which is made of ordinary metal instead of depleted uranium, which is applied in American ammunition and body with a plastic driving bands. At the same time, the first multi-shot is cumulative shell that holds an additional fairly strong fragmentation. Swiss chamber 140-mm gun is somewhat shorter than the assembly adopted by NATO countries, with all this according to the «Ordnance Enterprise,» this tool and projectiles to it as needed can be quite rapidly adjusted to the existing international standards on the bolt.
Leopard 2 with a 140-mm gun
The main efforts of Swiss engineers in the development of new weapons based on the analysis of external ballistics on final line of movement of ammunition kinetic act, possessing different structural features (width, weight, length, speed) tested against a range of targets. In addition, the impact of multi-purpose shells was investigated in static tests. Tests have shown that the new 140-mm ammunition in a position to penetrate the iron armor of up to 1000 mm, which is a significant increase in armor penetration, if associate with are in service with 120-mm shells. It should be noted that the Swiss 140-mm smoothbore gun is so far the only test gun. And given the considerable decrease in the danger of war in Europe since the beginning of its development in the foreseeable future, it will not be put into operation. Development of a 140-mm guns in England Over the years, a number of former British Ministry of Defense R & D management (DRA) worked on the project 140-mm cannon for the tank coming FTMA. Initially, it was planned to create tools that will be ready for production in first troops of the XXI century, but the collapse of the Soviet Union and the demise of the Warsaw Pact significantly slowed the work on the program there, as an instrument had been received in the industrial establishment. In England, implemented two applets: one of them funded by the Ministry of Defense and manage DRA, the major work on it took place from 1989 to 1992. Second example program was initiated by «Royal Ordnance» and ran from 1989 to 1993.
British Challenger 2 MBT, a 140-mm gun has not got
By early 1993, «Royal Ordnance» and DRA had a fire of his own 140-mm guns at the sites of the country. The company «Royal Ordnance» held about 120 rounds of ammunition APFSDS own 140-mm cannon mounted on a test board. This gun provides 40% armor penetration increase in comparison with 120-mm guns. 140-mm ammunition for the new guns were significantly heavier than the existing 120-mm shells were therefore made separate, consisting of 2-parts (projectile and charge), which is charged to implement using the autoloader. As it turned out the installation of a new 140-mm gun with an autoloader for tanks «Challenger-2» or M-1A1/A2 Abrams was very costly. On the new French tank «Leclerc» in the recess of the turret was mounted automatic loader, but the main gun of the tank remains a 120mm gun. It was assumed that the shells APFSDS, which were to be used in the tank coming FTMA, will have a core of depleted uranium. Such ammunition own best armor penetration, but coupled with the fact possess the highest cost of production and can not be used in peacetime for environmental reasons. 140-mm gun promising U.S. system ATAC In the U.S. system is a promising smoothbore tank gun caliber 140-mm (ATAC) consists of a gun XM-291, XM-automatic loader 91 and a family of new ammunition. It was assumed that this system will be 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 seamless installation and rollback mechanism that leads to firing ammunition, consisting of 2 parts (projectile and charge). Muzzle energy of the cannon is 2 times greater than the energy of a standard 120-mm gun M-256, which are armed with tanks «Abrams» M1A2. The gun has an extractor gunpowder smoke and heat insulating cover 91 kg. lighter than a standard M-256 guns.
140-mm gun XM-291 based on the Abrams tank
The originality of the system lies in the fact that after the substitution of the barrel (takes about an hour), this system can keep the fire of a 120-mm one-piece common and promising ammunition. The gun works in combination with automatic loading XM-91, which is able to recognize the elected types of ammunition. Mechanisms created by the transfer of ammunition «Lockheed Martin». In the recess of the turret contains 17 120-mm or 140-mm rounds, ready for immediate use, another 22 140 mm round of 2-piece or unitary munition 33-caliber 120 mm can be placed in the body of the tank. The introduction of automatic loader allows to reach the rate of fire at 8-12 rounds per minute. The family of ammunition for the ATAS system is 3-shells: cumulative projectile XM-965 projectile kinetic actions XM-964 and XM-training projectile 966. Every shot is of the charge and projectile. The charge is similar for all 3 rounds and consists of a detonator and a truncated base parts combustible side walls of the ignition system and a propelling charge. When fired, the sleeve is burned, leaving only basis. Snap connection with the projectile charge allows you to remove the shell from the breech end of the barrel. Seasoned standards developed by ATAC system are tested in the land forces of the U.S., with all this on an industrial scale 140-mm tank gun promising not done. 140-mm gun, «Bagheera», Ukraine In Ukraine, as were the development of instruments of caliber 140 mm. As a result, construction work came to light gun L55 «Bagheera» in the title of the figure 55 shows the length of the barrel in calibers. This gun is designed to upgrade existing weapons and promising models of armored vehicles. Considering the option of installing it on the T-84M «Hold», but realized he was not.
MBT Ukrainian T-84 The Citadel, a 140-mm gun has not got
Properties of the experimental tank gun oversized power L55 «Bagheera» Caliber — 140 mm. Barrel Length — 7000 mm. (55 gauge) Large recoil length — 310 mm. The initial velocity of the projectile — 1870 m / s. Kreshernoe pressure — 564 MPa Muzzle energy — 15.74 MJ Receiver weight BPS — 9 kg. Flight weight BPS — 7 kg.