Editing Machine gun (section)

=== Interwar era and World War II ===
[[File:Suomi M31 Torpin Tykit 2.JPG|thumb|[[Suomi KP/-31|Suomi M31]] [[submachine gun]] with 70-round drum magazine attached, 20- and 50-round box magazines]]
As better materials became available following the First World War, light machine guns became more readily portable; designs such as the [[Bren light machine gun]] replaced bulky predecessors like the Lewis gun in the squad support weapon role, while the modern division between medium machine guns like the [[M1919 Browning machine gun]] and heavy machine guns like the [[Browning M2]] became clearer. New designs largely abandoned water jacket cooling systems as both undesirable, due to a greater emphasis on mobile tactics; and unnecessary, thanks to the alternative and superior technique of preventing overheating by swapping barrels.

The interwar years also produced the first widely used and successful [[general-purpose machine gun]], the German [[MG 34]]. While this machine gun was equally able in the light and medium roles, it proved difficult to manufacture in quantity, and experts on industrial metalworking were called in to redesign the weapon for modern tooling, creating the [[MG 42]]. This weapon was simpler, cheaper to produce, fired faster, and replaced the MG 34 in every application except vehicle mounts since the MG 42's barrel changing system could not be operated when it was mounted.