A synchronization gear was a device enabling a single-engine tractor configuration aircraft to fire its forward-firing armament through the arc of its spinning propeller without bullets striking the blades. This allowed the aircraft, rather than the gun, to be aimed at the target.
The Lewis gun is a First World War–era light machine gun. Designed privately in the United States though not adopted there, the design was finalised and mass-produced in the United Kingdom, and widely used by troops of the British Empire during the war. It had a distinctive barrel cooling shroud and top-mounted pan magazine. The Lewis served to the end of the Korean War, and was widely used as an aircraft machine gun during both World Wars, almost always with the cooling shroud removed, as air flow during flight offers sufficient cooling.
The Vickers machine gun or Vickers gun is a water-cooled .303 British (7.7 mm) machine gun produced by Vickers Limited, originally for the British Army. The gun was operated by a three-man crew but typically required more men to move and operate it: one fired, one fed the ammunition, the others helped to carry the weapon, its ammunition, and spare parts. It was in service from before the First World War until the 1960s, with air-cooled versions of it on many Allied World War I fighter aircraft.
The FN Minimi is a Belgian 5.56mm light machine gun/squad automatic weapon developed by Ernest Vervier for FN Herstal. Introduced in the late 1970s, it is in service in more than 75 countries. The weapon is manufactured at the FN facility in Herstal and their U.S. subsidiary FN Manufacturing LLC.
The AEG J.I was a German biplane ground attack aircraft of 1917, an armored and more powerful version of the AEG C.IV reconnaissance aircraft.
The FN MAG is a Belgian 7.62 mm general-purpose machine gun, designed in the early 1950s at Fabrique Nationale (FN) by Ernest Vervier. It has been used by more than 80 countries and it has been made under licence in several countries, including Argentina, Canada, Egypt, India and the United Kingdom.
A firearm is said to fire from an open bolt if, when ready to fire, the bolt and working parts are held to the rear of the receiver, with no round in the chamber. When the trigger is actuated, the bolt travels forward, feeds a cartridge from the magazine or belt into the chamber, and fires that cartridge in the same movement. Like any other self-loading design, the action is cycled by the energy released from the propellant, which sends the bolt back to the rear, compressing the mainspring in readiness for firing the next round. In an open-bolt gun firing semi-automatically, the bolt is caught and held at this point by the sear after each shot; and in automatic open-bolt fire, it's caught and held in this manner whenever the trigger is released. In contrast to this, in closed-bolt guns, the trigger and sear do not affect the movement of the bolt directly.
A semi or full-automatic firearm which is said to fire from a closed bolt is one where, when ready to fire, a round is in the chamber and the bolt and working parts are forward. When the trigger is pulled, the firing pin or striker fires the round; the action is cycled by the energy of the shot, sending the bolt to the rear, which extracts and ejects the empty cartridge case; and the bolt goes forward, feeding a fresh round from the magazine into the chamber, ready for the next shot.
The Albatros C.III was a German two-seat general-purpose biplane of World War I, built by Albatros Flugzeugwerke. The C.III was a refined version of the successful Albatros C.I and was eventually produced in greater numbers than any other C-type Albatros.
The PK, is a belt-fed general-purpose machine gun, chambered for the 7.62×54mmR rimmed cartridge.
The Fokker E.I was the first fighter aircraft to enter service with the Fliegertruppe of the Deutsches Heer in World War I. Its arrival at the front in mid-1915 marked the start of a period known as the "Fokker Scourge" during which the E.I and its successors achieved a measure of air superiority over the Western Front.
The Maschinengewehr 08, or MG 08, was the German Army's standard machine gun in World War I and is an adaptation of Hiram S. Maxim's original 1884 Maxim gun. It was produced in a number of variants during the war. The MG 08 served during World War II as a heavy machine gun in many German infantry divisions, although by the end of the war it had mostly been relegated to second-rate fortress units.
The MG 3 is a German general-purpose machine gun chambered for the 7.62×51mm NATO cartridge. The weapon's design is derived from the World War II era MG 42 that fired the 7.92×57mm Mauser round.
The MAC mle 1931 machine gun, was a machine gun used in French tanks of the World War II era, as well as in fortifications such as the Maginot line. It is also sometimes known as the JM Reibel, from Jumelage de mitrailleuses, or Reibel twin-mounted guns and really refers to the specialized twin-mounting frame used in JM cloche cupolas on the Maginot Line fortifications, while MAC mle 1931 refers specifically to the gun. The JM twin-mounts were the standard emplacement for the mle 1931 in fixed fortifications, while tanks and other AFVs received single guns.
The Bergmann MG 15nA was a World War I light machine gun produced by Germany starting in 1915. It used 100- and 200-round belts and utilized a bipod, which allowed the weapon to be mounted on a flat surface for more accurate firing. It was briefly put back into service during the closing months of World War II in Europe by German Volkssturm units who lacked modern equipment and were little more than suicide squads meant to mount a hopeless last defense. Nazi Germany was using any weapon they had available during the last part of the war due to failing production and resupply.
The SIG MG 710-3 is a Swiss 7.62 mm general-purpose machine gun (GPMG) designed and manufactured by SIG - Schweizerische Industrie Gesellschaft. The weapon was developed as a commercial venture primarily for export, since the Swiss Army had already adopted the 7.5 mm MG 51 GPMG, produced by the federal arms factory W+F.
The 7.5 mm Maschinengewehr 1951 or Mg 51 is a general-purpose machine gun manufactured by W+F of Switzerland. The weapon was introduced into Swiss service when the Swiss Army initiated a competition for a new service machine gun to replace the MG 11 heavy machine gun and the Furrer M25 light machine gun adopted in 1911 and 1925 respectively.
The Fokker-Leimberger was an externally powered, 12-barrel rifle-caliber rotary gun developed in Germany during the First World War. The action of the Fokker-Leimberger differed from that of a Gatling in that it employed a rotary split-breech design, also known as a "nutcracker".
The M1919 Browning is a .30 caliber medium machine gun that was widely used during the 20th century, especially during World War II, the Korean War, and the Vietnam War. The M1919 saw service as a light infantry, coaxial, mounted, aircraft, and anti-aircraft machine gun by the U.S. and many other countries.
The Zeppelin-Lindau CS.I was a German single-engined reconnaissance seaplane with a low-wing monoplane layout.
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