Lewis machine gun .303
| 01. Original name | Lewis Gun | |
| 02. Other official names | Model 1915; M1917 in .30-06; M1918 Lewis ( aircraft version); M1918s | |
| 03. Popular names | Lewis automatic machine gun; Lewis automatic rifle | |
| 04. Chamberings | .303 British; .30-06; 7.92x57mm Mauser; 7.62x54mmR | |
| 05. Designed by | Colonel Isaac Newton Lewis; Samuel McLean; BSA company | |
| 06. Design date | 1911 | |
| 07. In service date(s) | 1915-1942 | |
| 08. Adopted by | Australia, Belgium, Canada, Czechoslovakia, Finland, France, German empire, Italy, Norway, Poland, Russian empire, United kingdom and British empire (all 8 marks) ,United States, New Zealand | |
| 09. Production quantities | Estimated 202,050; 50,000 WW1; 150,050 WW2 | |
| 10. Mechanism | Gas-operated long stroke gas piston, rotating open bolt; 97 round drum magazine | |
| 11. Weight | 13kg (28lbs) | |
| 12. Mountings | Bipod mounted; Tripod mounted for anti-aircraft use; Used in aircraft and light vehicles | |
| 13. Practicality in action | In field used considered too heavy for light machine gun use and complicated. Introduce mud and dust and there was a variety of malfunctions and stoppages. The ammunition supply mechanism was considered flawed and prone to miss feeding. They were best used in aircraft and boats due to the cleaner environment | |
| 14. Comments / Other information | Rates of fire were 5-600 rpm with mark 7 ammunition. Effective range of 880 yards and a maximum range of 3500 yards Rates of fire were sustainable with 47 or 97 round magazines The Lewis gun was produced in .303 British originally but for other markets around the world in .30-06, 7.92x57mm Mauser and 7.62x54mmR. Introduced 1915, chambered for the .303” Service round; 47-round horizontal drum magazine: cyclic rate about 550rpm; weight without magazine 27lb. It has the following unusual features, air-draft barrel radiator, clock-type return spring, and rotation of the magazine by movement of the bolt/piston group. |