french light machine gun in the first world war was crap

The Chauchat was not comparable to the submachine guns of World War I, which used pistol rather than rifle ammunition and were thus less powerful. The Italian Villar-Perosa and Beretta Model 1918, the first two submachine guns to appear in World War I, fired the 9 mm Glisenti (a less powerful version of the 9mm Parabellum).                                                                                                    The MP18 Bergmann, a German Army submachine gun fielded during the spring of 1918, fired the 9 mm Luger cartridge. Compared to the Chauchat, these early submachine guns were used in relatively small numbers (thousands rather than hundreds of thousands), and had much shorter effective ranges.

Unlike much heavier air-cooled and water-cooled machine guns (such as the Hotchkiss machine gun and the various belt-fed Maxim gun derivatives), and in common with the Lewis Gun, the Chauchat was not designed for sustained defensive fire.
 The tactical edge expected from the Chauchat was to increase the infantry's offensive firepower during the assaultbarclay with a machine gun made in hell

While the performance of the M1915 Chauchat in 8MM Lebel was considered acceptable at the time, the performance of the M1918 Chauchat in .30-06 was soon recognized as abysmal (and partly the reason for the gun's bad reputation) : the common problem was a failure to extract after the gun had fired only a few rounds and became slightly hot.

Based on archival records and recent trials, including a firing test performed at Aberdeen Proving Grounds in July 1973, the adaptation of the Chauchat to use .30-06 ammunition had been compromised by incorrect chamber measurements and sub-standard manufacturing.

 There has been no explanation as to why US inspectors at the Gladiator factory did not properly test fire these weapons as they were not rechambered M1915's but actually a whole new weapon based on the Chauchat design. The US Army is known for its thoroughness in testing weapons, but in this case either negligence or else the advanced knowledge that the Browning Automatic Rifle (BAR) would soon replace the Chauchat, anyhow,may have played a role.
 Only small numbers of the .30-06 Chauchat ever reached the front lines and they were immediately discarded by the troops as useless as they would only fire a few magazines before heating up and ceasing to function. As a result, the Chauchats in 8mm Lebel continued to be used by the AEF.Supplies of the newly manufactured and superior Browning Automatic Rifle (BAR) were allocated sparingly and very late, during the Meuse-Argonne offensive which begun in late September 1918. About 75% of the U.S. Divisions were still equipped with the Chauchat - in its original French M1915 version - at the Armistice of November 11, 1918.

It is also well documented that General Pershing had been holding back on the BAR until victory was certain, for fear it would be copied by Germany (Ayres, 1919). (wilson edward lewis gun
Other accounts, however, state that the reason that the BAR didn't see much combat was because the first units equipped with them simply didn't arrive until September.)[citation needed] However, it is also known that the very first BAR's delivered had improperly tempered recoil springs and had these guns been prematurely introduced during the summer of 1918, they might have also been viewed as problematic