Britain
1-pdr (0.45 kg) [1.46" (37 mm)] Mark 1
Updated 20 February 2008
"Pom-pom" gun that was originally made by Maxim and later taken over by Vickers.  This was basically a scaled-up version of the Maxim 0.303" (7.7 mm) Machine Gun.  Like the MG, the 1-pdr was belt-fed and recoil operated.

Extensively used as an AA weapon during World War I.
WNBR_1pounder_mk1_side_pic.jpg

1-pdr. on AA mounting at the Imperial War Museum in London, UK
Note air-cooled 40 mm Bofors at right
Photograph copyrighted by Shane Rogers
WNBR_1pounder_mk1_front_pic.jpg

Front view of 1-pdr at the Imperial War Museum
Photograph copyrighted by Vladimir Yakubov
WNBR_1pounder_mk1_id_pic.jpg

Identity Plate on above weapon

Q.F.I.P Mark II = Quick Fire 1-Pounder Mark II
VSM = Vickers & Sons, Maxim
Photograph copyrighted by Shane Rogers
.
Gun Characteristics
.
Designation VSM 1-pdr (0.45 kg) [1.46" (37 mm)] Mark I
Ship Class Used On Many
Date Of Design about 1890
Date In Service about 1895
Gun Weight N/A
Gun Length oa N/A
Bore Length N/A
Rifling Length N/A
Grooves N/A
Twist N/A
Length Of Rifling N/A
Chamber Volume N/A
Rate Of Fire Cyclic:  About 100 rounds per minute
.
Ammunition
.
Type Fixed
Weight of Complete Round N/A
Projectile Types and Weights HE - 1.39 lbs. (0.56 kg)
Bursting Charge HE - N/A
Projectile Length HE - N/A
Cartridge Case Type, Size and Empty Weight Brass, 37 x 94R mm, N/A
Propellant Charge N/A
Muzzle Velocity 1,204 fps (367 mps)
Working Pressure N/A
Approximate Barrel Life N/A
Ammunition stowage per gun N/A
.
Mount / Turret Data
.
Designation N/A
Weight  N/A
Elevation N/A
Elevation Rate Manually operated, only
Train 360 degrees
Train Rate Manually operated, only
Gun recoil N/A
.
Data from
"Naval Weapons of World War Two" by John Campbell
"US Naval Weapons" by Norman Friedman
"Rapid Fire" by Anthony G. Williams