Vickers Gas-Operated No 1 Mk I

An overview of the Vickers Gas-Operated machine gun – the Vickers K – is available on the Association’s YouTube channel.

The following table provides the official dates for the service of the Vickers GO; however, it’s clear that the gun was formally in service prior to 1945 and, therefore, it’s likely that this is when it was adopted for land service formally with retrospective approval.

Cat. No.IntroductionObsolescentObsoleteRemarks
Section C.1
L. of C. C.1027
18th January 1945
L. of C. C.2630
12th February 1946
L. of C. C.3375
10th November 1947
Aircraft gun, with spade grip

Length of gun overall with flash eliminator3 ft. 4 in.
Length of barrel1 ft. 8 in.
Weight of gun (approx).
(i) Mk. I, No. 1 gun
(ii) Mk. I, No. 2 gun
19.75 lb.
20 lb.
(i) Type
(ii) Twist
(iii) Number of grooves
Left hand
1 in 10 in.
Ammunition usedAll types of Mk. VII S.A.A.
Method of feedMagazine
Capacity of magazine(i) 60 rounds
(ii) 100 rounds
Speed of fire (approx.)
(i) Mk. I, No. 1 gun
(ii) Mk. I, No. 2 gun
(iii) Mk. I, No. 3 gun
(iv) Mk. I, No. 4 gun
950 rounds per min.
950 rounds per min.
950 rounds per min.
700 rounds per min.
Marks on the gun
(i) On the side of the breech casing
(ii) On the barrel
(iii) On the breech block
(iv) On various components
Nature, mark and number of the gun
Proof mark, Calibre, Year of manufacture (last two figures), Number of the barrel
Number of the breech block
Viewer’s marks, Broad arrow, Maker’s trade mark
SightsSeparate store
(i) Air service
(ii) Ground service
Turret or free installations


The GO No. 1 was originally a Royal Air Force observers gun as it had a high rate of fire which made it suitable for shooting at high speed planes and getting as many bullets on target in the short space of time in which a plane would have been visible and in range. There were two sizes of drum magazines which fed the gun, a 60-round version (the No. 1, Mk. 1) and a later 100-round version (the No. 2, Mk. 1), which is commonly described as a 96- or 97-round version as this was the number of rounds advised to be put into it in order not to weaken the spring and possibly cause stoppages. In approximately 1943, the Browning Machine Gun replaced the Vickers as the primary weapon in aircraft so they were effectively made redundant.


However, an ambitious young officer in the form of David Stirling formed the Special Air Service and he found that the GO No. 1 gun was an ideal weapon for the types of missions which they would be undertaking. The high rate of fire made it so the SAS troopers would be able to get as many bullets into the target without having to stay on the ground longer than necessary. The SAS mounted the guns on their jeeps usually in pairs with two at the front and two at the back and then a single piece was sometimes mounted on the drivers side wing so the driver could get provide additional support as necessary.

The Long Range Desert Group used the GO No. 1 in the same manner as the SAS.

Another user of the K gun in a jeep mounted role was the 1st Airborne Squadron of the Reconnaissance Corps attached to the 1st Airborne Division. This was the unit that took part in the ill-fated attack of Arnhem, Holland for Operation “Market-Garden” in September 1944. They mounted a single Vickers K gun on a cut-down ‘P.L.M.’ mounting on the bonnet of their jeeps. The Reconnaissance Corps carried the spare magazines for their guns in issue biscuit tins! They fitted perfectly and could hold about 6 to 8 in a tin and this was carried in the foot-well of the passenger side of the jeep.