Historic context :

The captain de Bange proposed and received the French Army approbation, from 1877 to 1885, of a brand new artillery system whose calibers were ranging from 80 to 270 mm. These various weapons had in common a new tube design (jacketted barrel) and a brand new interrupted screw breech with a plastic material obturation system that limited the gaz leaks , therefore improving the propulsive charge efficiency. They were however mounted on static rigid carriages without recoil recuperating system, unless wooden ramps under the wheels, and very rarely an external hydraulic brake was added between the carriage and the wooden platform to help the returning into firing position.

Although obsolete in 1914 when compared to the German heavy artillery weapons and the newest French guns, the Canon de 120 L modèle 1878 de Bange, designed for both flat fire and high angle fire, was remarkably precise and offered a good range.

Big quantities of these weapons were availabble mainly in the fortresses in 1914 (2296 guns, compared to the 120 guns allocated to the field army), it went back into service as a heavy fieldgun in the early 1914 war months, to solve the issue caused by the lack of heavy artillery in the French army trapped in a position war.

The wheels were most often equipped with 'cingolis' (wheel belts) in order to improve the mobility in soft grounds, participate to the gun stability during the firing, and somtimes replacing the heavy, long to install, and cumbersome wooden platform. This system was also operating as a recoil brake, thanks to the friction between the wheel and the belt.

A modified version appeared in 1916, with a simplified design barrel (without jackets), constant tube grooves angle, externally reckognizable by the transverse orientation of the tube handling ring (longitudinally oriented in the original version).

Present with 1480 guns in October 1916, and still with 526 items when the armistice came, the 120 Mle 1878 was still in service in 1940 in the Frenche army facing the modern Wehrmacht with these old equipments !

Technical data :

• Complete description : 120mm M 1878 (and 1878/16) siege and fortress long gun de Bange
• Design year : 1878 - 1878 mod. 1916
• Calibre : 120.00 mm
• Weight in firing position : 2700 kg (3500 kg with wheel belts)
• Weight for transportation : Same, tube set back on the carriage
• Tube length in calibres : 20.30 (Grooved part)
• Grooves : 36 to the right, progressive angle (end at 7 degrees) for tube 1878, constant angle 7 degrees for tube 1878/1916
• Projectile weight : 20.35 kg (obus allongé explosif en acier)
• Initial speed : 613 m/s
• Fire rate : 1 shot per minute
• Range : 12400 m
• Elevation range : -17 to +30 degrees
• Direction range :