Canon de 305 mm Modèle 1887
The Canon de 305 mm Modèle 1887 was a heavy naval gun used as the main armament of a number of French pre-dreadnoughts and coastal defense ships during World War I. Eight were converted to railway artillery in World War I and four were used during World War II. Construction. The "Canon de 305 mm Modèle 1887" 45 caliber gun was a typical French built-up gun of the period. It used a Welin interrupted-screw breech and separate loading bagged charges and projectiles. It was mounted in single gun turrets which had  a couple of unusual features. First, most of the turret's operating machinery was housed inside the turret, with only an armored tube to protect the ammunition hoists. This made little difference in the overall weight of the turret but did raise the machinery higher in the ship than the turrets of other nations, which did have implications for stability. Secondly, they used a hydraulic pivot to lift the turret when it rotated; this was lowered onto a seating ring when the turret was in the proper position to fire. Naval use. The mle 1887 equipped three French pre-dreadnought  battleships: The mle 1887 equipped two French coastal defense ships: Railway artillery. The Obusier de 370 modèle 1915 was a conversion of the mle 1887 by shortening the barrels to 25 calibers and boring them out to . It was proposed to convert eight gun barrels to railway artillery with another four spare barrels. The barrels for these guns would come from decommissioned ship's of the Charles Martel class of pre-dreadnought battleships and Bouvines class coastal defense ships. The work of building the guns was split between Schneider and Batignolles each producing four guns. There were slight differences between  the two groups of four guns. For example, a 370 mle 1915 with gun barrels from the battleship Charles Martel weighed 127 tonnes, while the others from the Bouvines class of coastal defense ships weighed 134 tonnes. Whether there were any ballistic differences between the finished pieces is unknown. The Obusier de 370 mm mle 1915 was considered a howitzer instead of a gun, so range and velocity were not primary considerations. Instead, high angle fire, projectile weight, and explosive yield were the primary considerations. Traverse was accomplished by using a section of curved track. Seven of the eight guns  survived the first world war and four were captured by the Germans during the second world war their designation was "37 cm H(E) 711(f)" and they used them throughout the second world war. Ammunition. The mle 1887 was equipped with three different types of shell: