3" Anti-Aircraft Gun Print
Written by David Boyd   
Thursday, 01 January 2009 14:50

The 3" Anti-Aircraft Gun

3 inch anti-aircraft gun

The 3 inch Anti-Aircraft dates back to the First World War and was still in service at the beginning of the Second World War. While the 3.7" was superior in performance to the 3" anti-aircraft gun the 3.7" was not yet available in sufficient numbers and the 3" was much lighter which meant it had greater mobility, it also had a high rate of fire and a good transverse speed. Production of the guns had ceased in Britain well before the war but a number were still undergoing conversion and mobile platforms were still being built at the beginning of the war. It's interesting to note that some guns were still being built in India up until 1943.

3" Anti-Aircraft Gun Data

Weight of gun and breech 2,250lb
Total length 140"
Length of bore 45 cal
Rifling 20 grooves, 1/30
Elevation -10, +90 degrees
Traverse 360 degrees
Weight in Action 6,000lb
Rate of fire  20-25
Projectile weight 16.5lb/12.5lb
Muzzle velocity 2,000/2,500fps
Max horizontal range 12,400/10,900 yards
Max Ceiling 15,700/23,500 feet

Armour Piercing ammunition

Ammunition Weight Angle Plate 500 1000 1500 2000
AP Mk II? 12.5lb 30 IT.80. 88 76 65 55

Production of 3" Anti-Aircraft guns by year (UK only)

  Pre-War Sep-Oct 1939 1940 1941
3" Gun Conversions 431 27 3 -
4 wheel platform 36 - 53 184
2 wheel platform 155 - 33 -
HE 1,223,038 152,324 344,937 -
Shrapnel 141,959 8,064 8,263 -

Sources - British & American Artillery of WWII, AVIA 22 456 - 514, WO 185/178