Vickers Mk I Heavy Machine Gun

The Vickers Mk I weapon used during the Great War was a simplified version of the gun designed by Hiram Maxim in 1883. This Maxim was both heavy and cumbersome, but was still adopted by the British Army in 1890: one per battalion. After the experience in the Boer War, the gun was redesigned. There were a number of detail changes, and the weight was also considerably reduced, and the wheeled carriage was changed for a tripod. It weighed 17.5kg (13kg without water in the cooling jacket), and 22kg when mounted on the tripod. The mechanism of the gun itself remained in all main respects unchanged, being a gas-operated, short­recoil type. The gun was water­cooled, holding seven pints of water in the cooling jacket. This water boiled after some 600 rounds had been fired, the steam was passed via a tube into a condenser can, from which it could be put back into the cooling jacket.

Ammunition came in 250-round webbing belts, and a theoretical maximum rate was 550 rounds per minute – but this was seldom attained, as it would quickly wear out the barrel. An experienced machine gunner would fire in bursts of some 25 rounds. It was best to fire some 50 rounds per minute, as this prevented too much mechanical strain or over­heating. After some 10.000 rounds fired the barrel had to be changed.

The original 0.303 in. Mk VII round gave a maximum range of 3,500 yards and a velocity of 2,440 fps. The streamlined Mk VIIZ introduced in 1916 increased the range by 1,000 yards. The .303 bullet would penetrate 2.03m of turf, 1.52m of clay, 0.76m of sand or 0.45m of wood. Traverse was governed by a clamp at the front upper part of the tripod. This could be locked tight or left free for a swinging traverse. Normally it was clamped loosely enough to allow the gun be “tapped” to the right or left by striking the gun hard handle with your hand. This would result in a series of overlapping bursts of fire. Loading and cocking could be completed in a few seconds once the weapon was mounted. A good crew could mount, load, lay, aim and fire the Vickers in 30 seconds. When in the line, the gun was often left mounted, half­cocked and camouflaged.

The great strength of the Vickers MG, in contrast to the Lewis gun or to simple rifle fire, was that it could be set up in advance for fixed fire tasks. Targets could be registered during the day, using the direction markings on the tripod's traverse ring, and the graduations on the elevating wheel. By night, or in fog or in smoke, the gun could be laid in the blind, and effective fire brought on to all ranges. For example, the forward edge of an wire obstacle could be set up on a bearing, so that the MG could enfilade any troops that got close to the wire. And in the same way gaps in the wire could also be very effectively covered.

Prior to the Battle of the Somme Vickers teams began to be employed as a sort of artillery, by providing high elevation fire to supplement the artillery barrage. With the new MK VIIZ streamlined bullet, fire could be placed more than twice as far out as the sighted maximum range of 2.000 yards.

Heavy Machine Guns of this type was not a really accurate weapons. In face of frontal attacks, their pretty limited speed of traverse made it possible for an attacker to advance on it in short rushes. (This was a tactic the Germans per­fected.) The use of enfilade fire from systems of mutually supporting machine gun nests or bunkers, was much more effective, and that type of positioning was actually the norm. The Vickers was at its most effective when firing at 800 to 1,200 yards, where a beaten zone was formed were most men standing up would be hit. (The bullets from such a burst hit the ground in a leaf-like pattern.)

It had problems. The MG:s high profile made it difficult to camouflage in a trench war­fare. At night a firing weapon emitted a big and very conspicous stream of flame. And in cold weather, once the water in the cooling jacket boiled, it gave off a plume of steam which hung in the air like a small, very tell-tale cloud.

The Vickers machine gun was an expensive and complex. In 1915 one gun cost to manufacture, each weapon comprising over 130 parts, each of which was machined to very fine tolerances from high-grade steels. Still, it was not too complex for the troublesome conditions of the First World War. The Vickers was used in every theatre of war from Gallipoli to Russia, from France to Mesopotamia, and it functioned well in all of them.

Main source: Martin Pegler: "The Vickers Machine Gun, 1914-18", in Military Illustrated August/September 1988 

Technical Data