Lewis Gun
Introduced in November 1915
Feed: 47 or 97 round drum magazine
Calibre: .303 inch
Cyclic rate: 600 rpm
Muzzle velocity: 2,240 ft/sec
Length: 50.5 inches (1283 mm)
Weight: 26 lbs. (11.8kg)
Range: Effective 3-400 yards

Vickers Gas Operated (Vickers 'K')
Introduced in August 1935
Feed: 100 or 50 round drum magazine, or 250 round metal link.
Calibre: .303 inch
Cyclic rate: 950-1100 rpm
Muzzle Velocity: 2,400 ft/sec
Length: 40 inches
Weight: 20.5 lbs. (9 kg)
Range: Effective 3-400 yards