US2399398A - Ammunition - Google Patents

Description

April 30,1946. w, SMITH 2,399,398

AMMUN IT ION Patented Apr. 30, 1946 UNITED STATES ATENT OFFHCE Application August 4, 1941, Serial No. 405,449 In Great Britain July 5, 1940 2 Claims.

This invention relates to guns and especially to the charge by which a shell (which term is intended to include all projectiles fired from guns) is fired from a gun.

In accordance with the invention, an explosive charge is enclosed in a casing which in use, fits within the breech of the gun and is held, during the initial expansion after the charge is fired, to provide a gas check and secure substantially com; 'plete combustion of the charge before the shell is moved.

The casing (or the forward part thereof) is expanded, when the charge is fired, into close contact with the breech of the gun and forms an obturator ring behind which the charge ex: pands.

One advantage of the improved charging device is that, since an obturator ring is formed by the casing, the shell need not be an exact fit in the bore of the gun which is especially advantageous when the gun is not rifled.

In the accompanying drawing which illustrates three preferred embodiments of the invention,

Figs. 1 and 2 represent in section and end view respectively a charge casing for a breech loading gun,

Fig. 3 shows a section through a similar casing for a breech loading gun employing finned shells,

Fig. 4 shows in section a charge casing suitable for a nozzle loading gun,

Fig. 5 shows a modified detail.

In the form shown in Figs. 1 and 2 the charge casing comprises a dish-shaped member A having a cylindrical wall B of such diameter as to fit fairly closely within the breech of the gun. This cylindrical wall is turned outwardly to provide an annular flange C.

Projecting centrally from the base of this dishshaped member is a cylindrical tube D. This central tube is intended to receive priming material (for instance, gunpowder) being retained by a paper disc E- The explosive charge, for example cordite, surrounds the tube and is held by a prepared paper container F.

The casing is closed by a back plate G which around its edge is turned over the annular flange C of the front part of the casing, for instance by spinning or stamping, locking the container F in position. This plate has a central aperture for the reception of a detonator H which is turned over a washer J. A removable protection disc K prevents damp from entering the casing and facilitates safe handling.

The charge case is connected to the projectile proper by a screwed sleeve L which engages a screwed spindle M which passes through the member L and has a flange N and a sealing P for the tube D. The breech cap is then closed and the flange C on the charge casing is held firmly between the breech cap and the end of the gun.

When the firing pin is operated the detonator H is caused to ignite the priming material in the tube D which in turn ignites the explosive'charge. As the explosive charge is completely enclosed, the initial expansion will take place only within the casing so that the expansion is checked until the pressure within the casing is suflicient to disrupt the joint between the two parts of the casing and to draw the forward part thereof out of the grip between the breech cap and the gun.

The forward part ofthe casing is then driven forward by the pressure generated by the gases and drives the shell forward out of the gun.

During the period when the casing is held, the internal pressure due to the combustion of the charge expands the cylindrical wall of the casing against the bore of the gun so that the front part of the casing when released forms an obturator ring behind which the gases expand. It will be seen that as the shell itself need be only a very slack fit in the gun bore, the resistance to the forward movement of the shell is very small.

Furthermore, after the casing is disrupted, the gases tend to expand the channelled edge of the back disc forcing the walls thereof into contact with the breech cap and the end of the gun barrel, thereby providing an effective seal at this position.

The check to the expansion of the gases ensures substantially complete combustion of the charge before the expansion occurs thereby increasing the expansive force eventually exerted to fire the shell. The invention thus provides a gas check for unrifled guns having an efiect similar to that provided during the initial combustion of the charge by the rifiing in rifled guns.

The charge casing may be of any suitable material though it is preferred to use brass or steel plate.

The forward part of the casing passes from the barrel with the shell and the back plate drops out when the breech cap is opened.

Referring now to the construction shown in Fig. 3 the case is very similar to that already described but the member A is shaped to engage a dished impact disc Q which is held in position by an impact spindle R screwed on to the spindle M.

Surrounding the impact spindle R is an impact tube S fitted inside the far end of the shell Z.

The charge case is pushed into the open end of the shell and is locked in position by a detent W carried on a spring link V secured by a screw Y to the impact spindle R.

The detent W engages one of the holes U between the fins T and is preferably loaded by a weight W.

In the form shown in Fig. 4 the charge casing comprises a dish-shaped member a having a cylindrical wall I) of such diameter as to fit fairly closely within the breech of the gun.

Projecting centrally from the base of this dishshaped member is a cylindrical boss c having a number of apertures d in its wall. This central boss is intended to receive a firing detonator e or firing cartridge which is inserted in a sleeve 9 screwed into the boss.

Priming material (for instance, gunpowder) is placed around the outside of this tube, being preferably enclosed in a sheath of paper for example, to keep it in position. The explosive charge, for example cordite, surrounds the priming material and may fill the space between the priming material and the cylindrical wall of the casing.

A flanged closure member I, issecured to the inner surface of the fiange b of the dish-shaped member and fits over the central boss and is secured in position by a hollow sleeve g engaging an internal thread on the boss, an appropriate number of washers h, ;i being interposed; these washers may be in laminations, starred on edges, or they may have conical corrugations.

The boss hasa projecting portion k of reduced diameter which passes through a hole in the base of the dished shaped member which is secured to the shoulder of the boss by a nut i or similar device. This projecting portion is is screwed into the shell proper,

The pressure of the gases causes the closure member 1 to bend back after breaking the joint with the wall b to a position indicated by dotted lines so that the member I passes out of the gun with the shell.

Referring now to Fig. .5 this shows a modified detail of the construction shown in Fig. 1. The screwed sleeve L and screwed spindle M are replaced by a screwed member I which has a projecting portion p which passes through the dishshaped member A and container F and is turned over a ring 72. On this ring fits a tube 111, for priming material provided with six holes q which are closed by a paper or like envelope until the detonator is fired.

The invention is not restricted to the details above described but includes all constructions and modifications coming within the ambit of the claims which follow.

I claim: I v I .1. A closed cylinder charge box for a projectile to be inserted into the breech of a gun, said box including a dish-shaped body having a cylindrical wall of a diameter slightly less than the diameter of the gun bore, an end plate, a separable end joint connecting the said wall and end plate and arranged wholly beyond the plane of the cylindrical wall, a priming material tube arranged centrally of the cylindrical wall and terminating shortof the end plate, a detonator carried solely by the end plate, and an explosivecharge carrier in the box and surrounding the tube the explosive charge carrier being destructible under the ignition of the explosive charge, said explosive charge carrier being arranged concentric with the priming material tube and of gradually increasing diameter towards the end plate.

2. A closed cylinder charge box for a projectile to be inserted into the breech of a gun, said box including a dish-shaped body having a cylindrical wall of a diameter slightly less than the di ameter of the gun bore, an end plate, a separable end joint connecting the said wall and end plate and arranged wholly beyond the plane of the Cylindrical wall, a priming material tube arranged centrally of the cylindrical wall and terminating short of the end plate, a detonator carried solely by the end plate, and an explosivech-arge carrier in the box and surrounding the tube, the explosive charge carrier being destructible under the ignition of the explosive charge, said explosive charge carrier being arranged concentric with the priming material tube and of gradually increasing diameter towards the end plate, and of the full diameter of the cylindrical wall adjacent the end plate.

WILLIAM HERBERT SMITH.

Images