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.

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.

[3] 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.