One weapon was destroyed in firing trials and the other was captured by the Germans after France surrendered in 1940 and used by them in the siege of Leningrad.

A number of crossbeams mounted on the underside of the carriage were jacked down and clamped to the track to increase the friction, when the carriage was forced backwards about a 1 metre (1.1 yd) from the recoil forces which were not absorbed by the hydraulic buffers on the gun cradle.

The mount was then jacked up and then moved back into firing position by hand-crank or electric motor.

[1] Elevation and ammunition handling were electrically powered from a separate generator car connected by approximately 10 metres (11 yd) of cables.

[2] The first howitzer was destroyed during firing trials at the range in Quiberon in July 1918, when a shell detonated prematurely in the barrel.