The shell consists essentially of two parts – (i) the body, and (ii) the burster container screwed into the nose of the shell and extending almost to the base of the shell cavity. The driving band consists of soft iron clad with copper on the outside. The burster con-tainer accommodates a bursting charge of four pressed pellets of picric acid weighing 78.5 grams (2 oz. 12.5 dr.). The four pellets are wrapped in a single wrapping of paper, about 0.005 inch thick, secured with an aqueous adhesive. The whole assembly is coa-ted with paraffin wax. The wrapping is marked "Kl.Ldg.Zd. K.Gr.Nb.".

The smoke mixture contained in the body of the shell surrounding the burster container consists of 80 parts of oleum absorbed in 20 parts of pumice. The method of charging appears to be as follows: The pumic is pressed into the shell body and the burster con-tainer screwed in. Oleum is introduced into the shell through a side charging hole, which is subsequently closed with a screwed plug.

The shell is coloured green, stencilled in black and white, and has a red ring above the driving band. The weight complete is 13 lb. 9 oz.

Fig. 17 – German 7.5 cm Smoke Shell

The cylindrical steel body has a screw thread at the front end for insertion in the burster container. The magazine filling of 16.8 grams P.E.T.N./Wax is in an aluminium container. The container is closed at the front end by the flange formed on the aluminium body of the detonator. The detonator fits into a cavity formed in the magazine filling and con-tains 0.6 grams of P.E.T.N. topped with 0.3 grams of lead azid/lead styphnate. The mouth of the detonator is closed by an aluminium cap which has four perforations lightly closed by a gauze disc. An aluminium washer between cardboard and paper discs is fitted over the detonator and retained by a leather washer. The leather washer is secured by turning over the mouth of the aluminium container.

Fig. 18 – German Gaine from 7.5 cm Smoke Shell

The fuze used is the kl.A.Z. 23 Nb. This has a combined direct and graze action and, ex-cepting the igniferous detonator, has no explosive filling. The aluminium body of the fuze, which is closed at the top by a brass cap, carries a wooden striker positioned over a steel needle secured in an aluminium holder. An aluminium plug screwed into the base of the body contains the brass graze pellet with its 3.16 grain igniferous detonator and re-ceives the pointed end of the needle. A steel spiral spring, fitted between the needle holder and graze pellet, keeps these two members apart during flight when the centrifu-gal safety segments have been swung clear. The five segments which prevent the need-le approaching the detonator in transport and in the bore are of aluminium and are pivo-ted on steel pins at the front end of the plug, where they are retained in the safe posi-tion by an expanding spring ring of phosphorus bronze. A flash hole is formed in the base of the plug.

Centrifugal force set up by the spin of the projectile in flight causes the spring ring to expand and permit the segments to rotate clear of the graze pellet, thus leaving the needle and graze pellet held apart by the spiral spring. On graze or impact the spring is compressed by the striker being driven in and the graze pellet setting forward. The flash produced by the needle piercing the detonator passes through the flash hole in the base of the plug to the detonator in the gaine. The recess in the underside of the needle hol-der fitting over the projection on the front of the graze pellet prevent the flash escaping in the wrong direction.

Detail of the cartridge and primer are given in the section describing the H.E. cartridge.

Fig. 19 – German Fuze for 7.5 cm Smoke Shell