The attachment should be removed from the gun and cleaned immediately after firing, all metallic fouling being carefully scraped away.
THE FUSEE SPRING.
On the left of the breech casing, the rear end being connected by the fusee chain and fusee with the crank, the front end is attached to breech casing by means of fusee spring box and adjusting screw which passes through front end of fusee spring box and through the nut at front end of spring.
To Weigh and Adjust.
Cock the lock, place loop of spring balance over knob of crank handle and pull vertically upwards, resting wrist on breech casing, the reading indicated when crank handle commences to move will be the weight of the fusee spring. This should be between 5 and 7 lbs. (for converted Mark I Guns between 10 and 12 lbs.).
If spring is over, or not up to weight, remove fusee spring box and adjust by means of adjusting screw, six turns making a difference of about 1 lb. (Turning screw clockwise increases weight and vice versa.)
The tension should always be kept as high as possible, consistent with maintaining the normal rate of fire (500 rounds per minute).
STRIPPING THE GUN.
The gun is stripped in the following order:—
Note.—All pins are driven in from right to left, and out in the reverse direction.