External finish and appearance of the Darne machine gun was crude, but worked well and its price was much lower than of any contemporary weapon with comparable combat characteristics.

Small numbers were also exported to Brazil, Spain, Yugoslavia, Italy and Lithuania, and captured French Darnes were used by German occupation forces for coastal defense.

The breech is locked by tilting the rear part of the bolt up into the mortise cut in the roof of receiver (similar to the M1918 Browning Automatic Rifle).

Infantry versions of the Darne machine gun were normally fitted with a pistol grip and rifle-type trigger below receiver, and a wooden buttstock.

Often criticized for its lack of reliability in the aircraft role, as other similar rifle calibers, the 7.5 mm bullets proved to be too light for air combat in World War II.