Three types of Fuze Wgr.Z. 50+ have been met with, each is similar in principles but dif-fers in detail. For convenience in reference they are referred to as type A, B and C. The fuze described in Pamphlet No. 13 is type B.

A plastic adapter is provided to enable the fuzes to be fitted in the standard 5 cm (1.96 inches) fuze hole, and a plastic container is also provided for packing in transport.

This fuze differs from type B, externally in its contour at about the flange and, internally in the shape of the needle holder, detonator holder and the centrifugal bolts with spring. The remaining components are similar to type B.

The base end of the needle holder is lengthened and recessed on its underside to form a sleeve accommodating the forward end of the detonator holder. The sleeve portion is provided with two radial holes through which pass the inner ends of two centrifugal bolts.

The detonator holder is reduced in diameter at the forward end and provided with a cir-cumferential groove to receive the inner ends of the centrifugal bolts when in the unar-med prosition.

The centrifugal safety mechanism consists of two bolts each with a spiral spring and se-curing plug. The bolts are accommodated in radial borings diametrically opposed in the fuze body so that in the unarmed position the bolts pass through the sleeve portion of the needle holder to engage the circumferential groove in the detonator holder. They are retained in this position by a brass spiral spring seated between the outer ends of the bolts end a screwed closing plug. The bolts and the plugs are recessed to form a seating for the spring.

Before firing. – The safety pin is withdrawn and the cap removed. The needle is separa-ted from the detonator by the centrifugal bolts which lock the needle holder and deto-nator holder together.

After firing. – During acceleration the needle holder sets back and prevents the outward movement of the centrifugal bolts until the projectile is well clear of the projector. When the centrifugal force is sufficient to overcome the friction between the needle holder and the bolts and the resistance of the springs, the bolts move outwards thus allowing the needle holder and detonator holder free movement. The needle holder moves forward slightly under the action of the creep spring which also prevents creeping of the deto-nator holder.

On impact the needle is forced on to the detonator by direct action. On graze the deto-nator is carried forward on to the needle, or it may be forced on to the needle by a side-ways movement of the inertia collar. The flash from the detonator passes through the central fire channel in the inertia collar and base plug to the gaine in the shell.

Note. – A red band around the needle holder is exposed when the fuze is in the armed position.

Fig. 4