The Soldier at the Western Front – The Use of Automatic Weapons
Source 4: Manual for the machinegun 08/15
If the gun is blocked during shooting, the blockage has to be removed immediately. The first maneuver is always:
Shake the lock handle and straighten the ammunition belt, if that won’t help, the box has to be opened for further checking ect.
Apart from that during shooting the weapon has only to be oiled and cleaned und water has to be refilled.
Every occurring break has to be used to clean and oil the cartridge carrier, the lock and whenever possible the barrel. The generously use of oil is recommended during shooting but don’t just spill it brainless in the box, till it’s dripping on the ground but generously oil the moving parts such as the lock, the cartridge carrier and the tilt-slide. Spread the oil abundant on the sides of the box and the sluts of the tilt-slide in a way that the existing sluts are filled with it. Chain, belt moving crank, belt mover and belt moving lever shouldn’t be forgotten when the weapon is oiled. After shooting
If it is expected that after the discharge the machine gun will not be used the gunner has to check that there is no more bullet in the chamber.
The barrel has to be oiled immediately and the machine gun has to be cleaned as soon as possible." Kriegsministerium. Allgemeines Kriegs-Departement: Leitfaden für das Maschinengewehr 08/15 (M.G. 08/15), 31.01.1917, Berlin 1917, p. 55