The 220 mm heavy field gun was a state-of-art design for its time, with decent traverse and capable of destroying fortifications or supporting infantry. The gun was split across two four-wheeled platforms, carrying cradle and barrel respectively, for transport. Platforms were designed to be towed by motor vehicles. For firing, the barrel - weighing - had to be transferred to the cradle platform. With the wheels raised the cradle sat directly on the ground. The Canon de 220 L mle 1917 utilized a hydraulicrecoil system, with the barrel assembly driven by recoil onto integrated incline against hydraulic brake and then sliding back under its own weight, thus limiting the maximum elevation. Loading was manual. Traverse of 20° was implemented with the rotating long base plate. For larger traverses, the wheels were lowered and the entire gun re-oriented.
History
After the lack of heavy artillery for infantry support in positional warfare of World War I had become obvious, the design was ordered by Frédéric-Georges Herr in 1917. The gun was built around an existing 220 mm design intended originally for the naval use. The manufactured pieces were distributed in 1917-1918 to the 151st Fortress Artillery Regiment and 166th Fortress Artillery Regiment. After the Armistice of 11 November 1918the guns were transferred to the 172nd Artillery Regiment. In the mobilization of 1939, the 48 surviving guns were assigned to the 173rd Artillery Regiment and 174th Artillery Regiment. Forty pieces captured by Germans were taken into service as 22-cm-Kanone 532. These guns were installed on full-traverse mounts for coastal defence. Sixteen guns were deployed on the Channel Islands with the rest deployed as part of the AtlanticWall. Four cannons were transferred to Italy where they were given the designation Cannone da 220/32 Mod. 1917.
One gun was manufactured as a prototype self-propelled gun. The Canon de 220mm L Mle1917 Schneider was the gun mounted on a tracked, but unarmoured, chassis with an optional armour shield. The engine allowed speed of, range of and decent cross-country performance. Although the performance was deemed satisfactory, the lack of self-propelled gun usage within the French Army lead to the prototype being put in storage, where it was captured by Germans in 1940 and scrapped after evaluation.
