British 3.7inch Mountain Howitzer

The initiative to get a new mountain howitzer came from the Indian branch of the British Army, which with their long experience of mountain warfare, wanted a more modern gun. Plans for a new design were drawn up already in 1906, and some tests were made, but due to shortage of funds the plans for a new mountain howitzer were shelved. Soon after the war started, though, the shortcomings of the old 10-pounder mountain gun was obvious, and a stop-gap solution was introduced, in the form of 2.75in gun, which was basically the old barrel mounted on a modern carriage. But as this soon proved very unsatisfactory, in 1915 it was decided to start producing the new 3.7in (94mm) mountain howitzer. It was first used in action in March 1917 and in 1918 some 70 guns had been issued to the war theatres in Mesopotamia and East Africa.

It was the first British artillery piece to use a split trail, giving it good elevation and a traverse of 20 degrees left or right. The 3.7 was a very fine design. It was the first British gun to use a split trail, which allowed for the high elevation needed for fighting in mountainous terrain. It also used separate ammunition with different charge options, which gave further possibilities to adjusting the trajectory of the shot. All this gave the gun a well-deserved reputation for high accuracy. The gun could shoot a 9.08kg heavy projectile some 5.4km’s. The 3.7 inch mountain howitzer also had a very smart suspension system, which let the four points of the gun (two wheels and two trail ends) to rest at different terrain levels and still stand solid. It also had a hydro­pneumatic, variable-recoil recuperator plus a large shield – but it was often removed. The gun could be elevated between -5° and +40° and had a traverse of 40°.

For mule carriage the barrel was split into two pieces, of 96kg and 98kg respective, and the rest of the weapon was then split into a further four loads. It weighed 779kg emplaced. On roads it could be pulled by two horses. It was much used during the inter-war years and during World War II, and it is a proof of the excellence of the howitzers design that it was not declared obsolete until 1960.

The beautifully preserved gun in the photos below can be seen in the fine Royal Artillery Museum in London, and were taken by Phil Radley.