Automatic Weapons

firearms in which the power of the gas of explosion at firing is used not only to impart movement to the bullet (projectile) but also to reload the weapon and produce the next shot. An automatic weapon can be used for continuous and for single-shot firing. A weapon in which only the loading operation is automatic is called a semiautomatic, or self-loading, weapon (as distinct from an automatic, or self-firing, weapon). The main characteristic of an automatic weapon is a high rate of fire, which makes it possible to hit a rapidly moving target and to create a great density of fire.

Cartridges are fed into an automatic weapon either by means of a magazine (or cartridge chamber) or by a flexible metal or canvas belt. Magazine feeding is used in automatic weapons that are not designed for a high rate of fire, such as pistols, submachine guns, rifles, carbines, light machine guns, and automatic medium-caliber cannons. Belt feeding is used in weapons with a high rate of fire, such as heavy machine guns, large-caliber machine guns, and small-caliber automatic cannons. The first automatic weapons were produced in the second half of the 19th century. An American, R. Pilon, designed an automatic rifle in 1863. In Russia the first automatic rifle was designed by D. A. Rudnitskii in 1887. In the early 20th century, armies of several countries began widely using the Madsen semiautomatic machine gun rifle, which was also adopted by the Russian army, But the most widely used automatic weapon was the Maxim heavy machine gun (invented by H. Maxim, an American, in 1883). The great combat value of automatic weapons was demonstrated in practice for the first time in the Russo-Japanese War of 1904–05, in which first the Russian and then the Japanese army used heavy machine guns. From then on, automatic weapons, in the form of heavy machine guns, rapidly became standard weaponry in the small arms system of armies. Intensive work to create light automatic weapons started in Russia a few years before World War I. In 1910–11 several Russian-designed automatic rifles were tested in Russia, including systems by V. G. Fedorov, F. V. Tokarev, Roshchepei, Shchukin, and Frolov. Fedorov’s automatic rifle proved the best of all those tested. During World War I, Fedorov designed a new automatic rifle, which was used in combat.

Armament technology has seen a great development in the USSR. There have been many brilliant designers, whose automatic weapons were used in the Great Patriotic War of 1941–45: V. A. Degtiarev, F. V. Tokarev, G. S. Shpagin, S. G. Simonov, B. G. Shpital’nyi, P. M. Goriunov, A. I. Sudaev, and others. The automatic weapons used today have been designed by M. G. Kalashnikov, E. F. Dragunov, N. F. Makarov, and others. The theory of designing automatic weapons first proposed by A. A. Blagonravov and developed in the works of E. L. Bravin, V. S. Pugachev, M. A. Mamontov, and E. A. Gorov has been of great importance in the development of modern automatic weapons. Among the capitalist armies that fought in World War II, automatic weapons were most widely used by the German army. The modern armies of developed states use only automatic and semiautomatic weapons.

Automatic weapons are divided into the following categories, depending on their combat employment: automatic pistols, submachine guns, automatic rifles (carbines), semiautomatic rifles, machine guns (light, heavy, and large-caliber), and automatic cannons.

The automatic system depends largely on the use of the power of the explosion gases. Modern automatic weapons can be divided into the following types:

(1) Weapon systems in which the automatic action is based on the use of the recoil of the barrel. These systems have a movable barrel, which is tightly fastened to the bolt at the time of firing. The blow-back of the bolt and barrel under the influence of the recoil, and the return under the action of return springs, provide for automatic ejection of the used cartridge cases, feeding the next cartridge into the cartridge chamber, and closing the bolt. These systems are divided into systems with a long barrel travel and systems with a short barrel travel (for instance, the TT pistol and the Maxim medium machine gun).

(2) Weapon systems in which the automatic action is based on the recoil of the bolt. In these systems the barrel is immovable. At the time of the firing, the bolt is either not engaged at all with the barrel (free bolt; for instance the Degtiarev submachine gun model 1940 and the Shpagin submachine gun model 1941), or is so fixed that it disengages under the pressure of the explosion gases on the bottom of the cartridge case (semifree bolt; for instance the British Thompson submachine gun model 1928).

(3) Weapon systems in which the automatic action is produced by the escape of the explosion gases into a gas chamber usually located in the front part of the barrel. The gases enter the chamber through escape apertures in the barrel after the bullet passes the apertures. The gas chamber has a mobile piston linked to the carrier rod (for instance, the Degtiarev submachine gun model 1927 and the Kalashnikov submachine gun) or through the bolt arm (for instance, the Shpitarnyi-Vladimirov heavy machine gun). Under the pressure of the explosion gases, the rod moves back, together with the bolt arm, and thus opens the bolt and ejects the cartridge case. The reverse movement of the movable parts and the loading are produced by a return spring. This type of automatic system has shown high performance qualities and is therefore widely used in modern models of automatic weapons. The high fire rate of automatic weapons causes a rapid overheating of the barrel. A cooling system is, therefore, very important. The first models of heavy machine guns usually had water cooling. This often complicated their use in combat if there was no water and also made the weapons heavier and bigger. Modern machine guns and other automatic weapons usually have air cooling. In general-purpose machine guns, heavy as well as light, the overheated barrel can be changed in combat conditions.