A machine gun is a fully automatic mounted or portable firearm, usually designed to fire rounds in quick succession from an ammunition belt or large-capacity magazine, typically at a rate of several hundred rounds per minute.

It would not be until the mid-19th century that successful machine-gun designs came into existence. The key characteristic of modern machine guns, their relatively high rate of fire and more importantly machine (automatic) loading, came with the Model 1862 Gatling gun, which was adopted by the United States Navy. These weapons were still powered by hand; however, this changed with Hiram Maxim's idea of harnessing recoil energy to power reloading in his Maxim machine gun. Dr. Gatling also experimented with electric-motor-powered models; this externally powered machine reloading has seen use in modern weapons as well. The Vandenburg and Miltrailleuse volley (organ) gun concepts have been revived partially in the early 21st century in the form of electronically controlled, multibarreled volley guns. It is important to note that what exactly constitutes a machine gun, and whether volley guns are a type of machine gun, and to what extent some earlier types of devices are considered to be like machine guns, is a matter of debate in many cases and can vary depending which language and exact definition is used.

Here are gun list we've got for you.

Besa
Besal
Breda 30
Breda M37
Bren
CETME Ameli
Charlton Automatic Rifle
Chauchat
CIS 50MG
Ckm wz.30
ZW-762
Darne
DS-39
DShK
EMERK
Fiat-Revelli Modello 1935
FM 24/29
FN MAG
FN Minimi
GatMalite
Gordon CSWS
Heavy s
Heckler & Koch HK121
HK21
Hotchkiss M1909
Hotchkiss M1914
Howell Automatic Rifle
Huot Automatic Rifle
K3
KG/1940
Kord
Ksp m/42
Kucher Model K1
Lahti-Saloranta M/26
Lewis
Light
LSAT
M1917 Browning
M1918 Browning Automatic Rifle
M1919 Browning
M2 Browning
M249 Squad Automatic Weapon
M60
MAC 1934
MAC-58
Madsen
Medium
Mendoza RM2
MG 131
MG3
MG4
MG51
Negev
NSV
NTK-62
Perino Model 1908
QBB-95
Reider Automatic Rifle
RMG .50
RPD
RPK
Salvator-Dormus M1893
Schwarzlose MG M.07/12
SG-43 Goryunov
SIG MG 710-3
Skoda M1909
St. étienne Mle 1907
Sterling 7.62
Stoner 63
Stoner LMG
Type 80
Type 99 Light
Uirapuru
UKM-2000
Ultimax 100
Vektor SS-77
Vickers
Vickers-Berthier
VMG-27
W85
Weibel M/1932
Zastava M72
Zastava M84
ZB-50