(Fig. 24)

The shell is fired from the separate-loading Q.F. 75 mm 27 calibre field gun. The stream-lined body of the shell has a narrow driving band of copper and is fitted with a dome-shaped impact cap. The body is coloured the normal pale blue with a white band imme-diately above the driving band. The impact cap is bright red. The designation of the equipment "75/27", and the nature of the bursting charge, "TRITOLITE", are stencilled in dark blue on the body. The length of the shell is 10 inches and the weight, filled, is 10 lb. 3 oz.

The shell body is of forged steel with a mild steel plate pressed in at the base and a left-hand external screwthread at the head to receive the impact cap. The cavity for the bursting charge is increased in diameter near the head and has a steel adapter for the fuze sweated with solder near the base. The impact cap is of aluminium alloy and is stepped internally to engage the flange on the cavity liner.

The cavity liner is pressed from 1 mm mild steel plate and is roughly parabolic in shape.

The bursting charge weighs 1 lb. 0 oz. 6 dr. and consists of cyclonite/T.N.T./ wax, the percentage of each being 58, 40.5 and 1.5 respectively. The filling is cast with the fuze and exploder assembled in the cavity.

The exploder consists of approximately of cyclonite/wax, 95/5, in the form of two pellets in a paper wrapper. The upper pellet is solid, whilst the lower has a cavity in the base to fit over the gains fitted to the fuze. An aluminium sheath, shaped to fit around the pellet and form a liner for the gaine cavity, is fitted over the base end of the lower pellet.

The fuze is screwed into the adapter in the base of the shell cavity with a left-hand screwthread and is fitted with a gaine which enters the cavity in the exploder. Details of the fuze and gaine are not yet available.

The perforation performance against homegeneous armour plate is estimated to be 55 mm at the normal and 50 mm at 30 degrees to the normal.