Historic context :

Initiallly designed as a landing light gun, the '1-pounder 37mm Mark A Model 1' semi-automatic light gun created by Bethlehem in 1916 was mainly used as an infantry gun by the US troops on the west front in 1918.

Its relatively heavy weight (about the double of the one of the French 37mm Mle 1916 gun that was also used by the US) probably limited its use as an infantry accompaining weapon. On the other hand, the extended length of the tube (42 calibres) was giving it very good ballistic properties (including a high 640 m/s initial speed), making this gun particulirarly well adapted to an anti-tanks mission.

Another interesting characteristic of this gun was the absence of vertical or horizontal aiming toothed wheels mechanism : the tube was linked to the carriage via a pivot yoke and a ball stud, and was handled as a machinegun by the servant, placing its shoulder against a rifle butt.

This gun seems to have been used also by the French army, whose 37mm Mle 1916 was lacking punch for the anti-tank fire. A 100 guns order was being manufactured in 1917, and a second larger one of 1000 guns was passed in 1918. Few of these saw service as they were largely seized by USA army for its own use or sent back to America as a war debt payment.

Technical data :

• Complete description : 1-pounder 37mm Mark A Model 1 Bethlehem
• Design year : 1916
• Calibre : 37.00 mm
• Weight in firing position : 441 kg (incl. 78 kg for the barrel and the breech)
• Weight for transportation :
• Tube length in calibres : 42.00 (rifled part)
• Grooves : 12
• Projectile weight : 0.48 kg
• Initial speed : 640 m/s
• Fire rate :
• Range : 3750 m
• Elevation range : -5 / +15 degrees
• Direction range : 45 degrees total range

• A gun for all nations - The 37 mm Gun and Ammunition - Volume II - 1914-1926           Robert A Mellichamp                     2012  
• Wikipedia http://fr.wikipedia.org/                           
• Les engins de tranchée de faible puissance 2ème partie, les engins à tir tendu - Guerre, Blindés et Matériel Nr 123       Général Guy François                   Histoire et Collection   2018