The Chauchat-Ribeyrolles 1918 submachine gun is a French prototype automatic weapon.

In 1918, they presented a "pistolet-mitrailleur" (submachine gun), meant to be used for close-range protection for the French tank crews.

The trials continued until 1919 with a weapon using the same magazine as the Chauchat.

The results were satisfactory but the weapon was too powerful for the intended self-protection use.

A mix of standard and tracer bullets was planned to be used to assist in aiming.