Vickers .50 Mark 3

These mountings first appeared in double barreled versions in the Van Amstel-class minesweepers in 1936, later also in the Tromp-class cruisers. The guns were ineffective, low rate of fire and effectiveness, and were later in the war replaced by British of American built 20 mm Oerlikons. It also appeared in quad versions on the Isaac Sweers and N-class destroyers.

Click to enlarge
Quad mount on a British destroyer

Gun specs
Gun type Vickers watercooled Mark 3 machine gun
Purpose Light AA-defence
Bore .50 calibre ( 12,7 mm )
Classes used on Double version: Van Amstel-class minesweepers
Tromp-class cruisers
( More ships projected )
Quad version: Isaac Sweers
Date of design Origin dates back from early World War I
Date in service 1936 ( first appeared on Van Amstel-class )
Length 62 calibers ( 1,32 m )
Gunweight 28,1 kg ( max )
Initial velocity 2520 feet/sec
Rate of fire 700 rounds/minute per gun
Cooling Watercooled
Shell specs
Shell types Non-explosive bullets
Shell weight 8 grams
Effective range 732 m
Range 1350 m @ 0 degrees
914 m @ 80 degrees
Mount specs
Mount type Quad mount: Mark III
Double mount:  
Mount armor -
Mount weight Mark III: 1,3 tons
   
Elevation Mark III: -10 / + 80 degrees
   
Train Mark III: continuous 360 degrees
   
Train method Mk III manual
Double mount: Power operated

Diagram
Click to enlarge
Octuple Vickers .50*
A Sight Linkage
B Elevation scale
C Elevation arc connected No 2 gun. All guns are connected by parallel linkage
D Layer's body rest
E Elevating handweel
F Training clutch lever
G Safety firing cam rail
H Mounting jumping clip
I Housing locking bolt
J Cam roller follower
K Safety firing linkage
L Guard tray under ammunition drum
M Spent cartridge tray
N Ammunition drum
* The octuple version was never used on a Dutch warships, but this particular diagram shows the details particularly well

Sources

HMS Andrew

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