|US M1918 Chauchat|
|French Model 1915 Chauchat|
The muddy trenches of northern France exposed a number of weaknesses in the Chauchat's design. Construction had been simplified to facilitate mass production, resulting in low quality of many metal parts. The magazines in particular were the cause of about 75% of the stoppages or cessations of fire; they were made of thin metal and open on one side, allowing for the entry of mud and dust.
In hopes to correct the problems the US M1918 Chauchat was redesigned to use a box magazine and chambered in 30-06. Development and production were rushed, and a large number of guns went out the door with incorrectly sized chambers. They were cut slightly too short, which meant that the neck of the cartridge case was jammed too tightly into the end of the chamber. Upon firing, the case would stick in the chamber and its rim ripped off by the extractor. The barrels also did not have extractor cuts in the barrel face, which didn’t help anything. They functioned so poorly that few, if any, made it into combat.