Editing Machine gun (section)

=== Maxim and World War I ===
[[File:Armouredgermanmachinegunnerworldwari.JPG|thumb|left|A model of a typical entrenched [[Germany|German]] machine gunner in World War I. He is operating an [[MG 08]], wearing a [[Stahlhelm]] and [[cuirass]] to protect him from shell fragments, and protected by rows of [[barbed wire]] and [[sandbag]]s.]]

The first practical self-powered machine gun was invented in 1884 by [[Sir Hiram Maxim]]. The [[Maxim machine gun]] used the recoil power of the previously fired bullet to cycle rather than being hand-powered, enabling a much higher rate of fire than was possible using earlier designs such as the [[Nordenfelt gun|Nordenfelt]] and Gatling weapons. Maxim also introduced the use of water cooling, via a water jacket around the barrel, to reduce overheating. Maxim's gun was widely adopted, and derivative designs were used on all sides during the First World War. The design required fewer crew and was lighter and more usable than the Nordenfelt and Gatling guns. First World War combat experience demonstrated the military importance of the machine gun. The United States Army issued four machine guns per regiment in 1912, but that allowance increased to 336 machine guns per regiment by 1919.<ref>{{cite book |last=Ayres |first=Leonard P.|title =The War with Germany |url=https://archive.org/details/cu31924027816820 |publisher =United States Government Printing Office|edition =2nd |date =1919 |location =Washington, D.C. |page =[https://archive.org/details/cu31924027816820/page/n70 65]}}</ref>

[[File:Vickers machine gun crew with gas masks.jpg|thumb|[[UK|British]] [[Vickers machine gun]] in action near [[Ovillers]] during the [[Battle of the Somme]] in 1916. The crew is wearing [[gas masks]].]]
Heavy guns based on the Maxim such as the [[Vickers machine gun]] were joined by many other machine weapons, which mostly had their start in the early 20th century such as the [[Hotchkiss machine gun]]. [[Submachine gun]]s (e.g., the German [[MP 18]]) as well as lighter machine guns (the first light machine gun deployed in any significant number being the [[Madsen machine gun]], with the [[Chauchat]] and [[Lewis gun]] soon following) saw their first major use in [[World War I]], along with heavy use of large-caliber machine guns. The biggest single cause of [[Casualty (person)|casualties]] in World War I was actually artillery, but combined with [[wire entanglement]]s, machine guns earned a fearsome reputation.

Another fundamental development occurring before and during the war was the incorporation by gun designers of machine gun auto-loading mechanisms into handguns, giving rise to semi-automatic pistols such as the [[Borchardt C-93|Borchardt]] (1890s), automatic [[machine pistol]]s and later submachine guns (such as the [[Beretta 1918]]).

Aircraft-mounted machine guns were first used in combat in [[World War I]]. Immediately this raised a fundamental problem. The most effective position for guns in a single-seater fighter was clearly, for the purpose of aiming, directly in front of the pilot; but this placement would obviously result in bullets striking the moving propeller. Early solutions, aside from simply hoping that luck was on the pilot's side with an unsynchronized forward-firing gun, involved either aircraft with pusher props like the [[Vickers F.B.5]], [[Royal Aircraft Factory F.E.2]] and [[Airco DH.2]], wing mounts like that of the [[Nieuport 10]] and [[Nieuport 11]] which avoided the propeller entirely, or armored propeller blades such as those mounted on the [[Morane-Saulnier L]] which would allow the propeller to deflect unsynchronized gunfire. By [[Fokker E.I|mid 1915]], the introduction of a reliable [[Synchronization gear|gun synchronizer]] by the [[Luftstreitkräfte|Imperial German Flying Corps]] made it possible to fire a closed-bolt machine gun forward through a spinning propeller by timing the firing of the gun to miss the blades. The Allies had no equivalent system until 1916 and their aircraft suffered badly as a result, a period known as the [[Fokker Scourge]], after the [[Fokker Eindecker]], the first German plane to incorporate the new technology.