Historic context :

The new 'Commission des Nouveaux Matériels' ('New Materials Commission'), created by the French parliament at the end of 1910 under the pressure of Army officers concerned by the lack of heavy field guns in their country order of battle, launched several successive modernisation programs. The last one (1913) planned between other projects a new carriage for the de Bange 155 L Mle 1877 barrel, and the creation of a new heavy field gun with a caliber from 130 to 140 mm and a long range (17 to 18 km).

The Etablissements Schneider, that were in the process of making the army approve their very good 105 L Mle 1913 inherited from a gun developped for Russia, takes out in its files a 'canon de 150 mm long Schneider (type SC 150 Nr2)' presented to Spain in 1910, itself derivated from a 'canon de 6 pouces de siège (type SC 6)' sold to Russia. The Commission des Nouveaux Matériels only retained the carriage to modernize the canon de 155 mm L Mle 1877 de Bange barrel : an economy-driven choice more than a technical one, this accurate fire tube being limited in range.

The 'canon de 155 L Mle 1877/1914 sur affût Schneider' ('on Schneider Carriage') that resulted from this assembly only came in operations in April 1916 with 120 such weapons, and was limited to a 13600 m maximum range.

As soon as 1915, the Etablissements Schneider resumed the study of the 150 SC Nr2 gun, aiming to satisfy better the specification for the new long range heavy field gun. The canon de 155 L Mle 1877/1914 carriage was kept almost untouched, but it was finally equipped with a new and longer Schneider barrel with an improved de Bange breech. This design gave birth to a very good long range heavy gun, named 'Canon de 155mm L Mle 1917 Schneider' although it has been adopted already in 1916.

The new gun was equipped with the good recoil recuperation system developped by Schneider for its Russian deliveries, with a long and slow recoil of the whole package composed of the tube and the recuperator body inside a long craddle overhanging far behind the breech block. The range increase was important since it went to 15900 m for the new generation 155 L, but at the cost of the weight that also increased from 6018 to 8718 kg and now needed to be transported into 2 separate loads.

The canon de 155 L Mle 1917 arrived on the front during the second half of 1917, and became the standard material of the Horse Heavy Industry, soon joined by the 155 L GPF for the mecanically towed units. The French Army still had 535 such guns in 1940...

Technical data :

• Complete description : 155mm Mle 1917 Long gun Schneider
• Design year : 1916
• Calibre : 155.00 mm
• Weight in firing position : 8718 kg
• Weight for transportation : 12620 kg, in two separate loads
• Tube length in calibres : 23.80 (rifled part only), 29.8 total length
• Grooves : 48 7 degrees, oriented to the right
• Projectile weight : 43.1 à 44 kg
• Initial speed : 550 et 650 m/s
• Fire rate : 3 rounds per minute
• Range : 15900 m
• Elevation range : -5 to +40 degrees
• Direction range : 4.3 degrees range