defences and mounted on a rail car to support the British assault on Boer defenses at Belfast, north-east of Johannesburg, but the battle ended before it could get into action. World War I The outbreak of the First World War caught the French with a shortage of heavy field artillery. In compensation, large numbers of large static coastal defense guns and naval guns were moved to the front, but these were typically unsuitable for field use and required some kind of mounting. The railway gun provided the obvious solution. By 1916, both sides were deploying numerous types of railway guns. France During the First World War France produced more railway guns in more calibers and with different mountings than everyone else combined. The largest French gun produce by Schneider of France the Obusier de 520 modèle 1916, a 20-inch (520 mm) railway "Fort Buster" to do what the German 16.53-inch Big Bertha had done at the outbreak of World War I and reduce the German forts in the final line of German defenses. One was destroyed in trials and the other did not complete firing trials prior to the signing of the Armistice. The gun remained in storage and was captured by the Germans during World War II. It later formed part of the German artillery complement during the Siege of Leningrad. The gun was disabled by a premature detonation and later abandoned. United States Baldwin Locomotive Works delivered five 14"/50 caliber railway guns on trains for the United States Navy during April and May 1918. Each 14"/50 gun mounted on a , rail carriage with four 6-wheel bogies was under the command of a United States Navy lieutenant with a standard U.S. Army 2-8-0 locomotive, a 10-ton crane car, two armored ammunition cars carrying 25 shells each, two cars carrying the recoil pit foundation materials, two fuel and workshop cars, three berthing cars, a kitchen car, a commissary car, and a medical dispensary car. A sixth locomotive pulled a headquarters car for Rear Admiral Charles Peshall Plunkett, with a machine-shop car, a spare parts car, a berthing car, a kitchen car, a commissary car, and a medical dispensary car. After delivery by ship, these trains were assembled in St. Nazaire in August and fired a total of 782 shells during 25 days on the Western Front at ranges between . Each projectile weighed and was fired at per second.