GB2138547A - Blank cartridges - Google Patents

Abstract

A blank cartridge comprises a projectile secured in the mouth of a cartridge case 2 by a threaded connection 5, 6. The screwthreads may be secured with adhesive. <IMAGE>

Description

SPECIFICATION Blank cartridge The invention relates to a blank cartridge for fire-arms, in particular automatic machine guns, with a projectile part and a cartridge case connected to the latter.

Blank cartridges are used both for handling drill as well as for weapons operation drill, which blank cartridges resemble the cartridges for live ammunition as regards shape, mass and position of the centre of gravity. It is thus intended to create conditions close to reality for the person practising, without any risk. Furthermore, the blank cartridges serve for checking loading actions, loading performance and the ejection speed of the cartridges. For checks of this type and in order to carry out ballast checks, for example of aircraft loaded with ammunition, maintaining specific parameters of live ammunition, such as mass, shape and position of the centre of gravity is of significance. Furthermore, blank cartridges should be able to withstand the aforesaid loads repeatedly; they must therefore be reusabie.

The known blank cartridges differ essentially by four construction principles: - the blank cartridge consists of solid material, for example aluminium, in order to be able to simulate the required mass of the cartridge. It also has a wear-resistant surface coating.

- The blank cartridge consists of a rotary member which is drilled to make it hollow and has the external geometry of a cartridge and a plug in the region of the base of the cartridge case.

-The blank cartridge has a projectile cap with a counter-balance mandrel of steel which is screwed in, which projects into an aluminium rotary member constructed as a sleeve.

-The blank cartridge consists of the original parts, namely projectile and propellant charge casing, which are connected to each other by a tie-rod for reasons of stability and balancing the mass of the cartridge.

These relatively complicated solutions are all based on the demand for the current standard for live ammunition; maintaining the shape, maintaining the mass and maintaining the position of the centre of gravity.

It is therefore the object of the invention to provide a blank cartridge of the aforementioned type, which is simple to produce from the technical point of view with few means and which fulfils the aforementioned requirements with regard to stability, shape, mass and position of the centre of gravity.

This is achieved according to the invention by screwing of the projectile part of the cartridge case at their common separating point, which is located at places where there is a reduction in the diameter, transition points in the diameter or at peripheral edges or recesses in the outer contour of the blank cartridge, due to which the separating point is invisible from the outside. Furthermore, when high stability is achieved, disturbing influences on the operation of the blank cartridge are avoided.

The external screwthread of the projectile part may be provided on the shoulder whereof the diameter is reduced to such an extent that the cartridge case screwed to its internal screwthread has the same outer diameter as the outer diameter of the projectile part.

In order to avoid accidental detachment of the projectile part and cartridge case, the threads which are screwed one to another may be secured with an adhesive. A seal against the internal formation of rust is thus formed simultaneously.

The marking bores provided in the cartridge case on the outer periphery may be blind bores, in order to prevent foreign bodies or moisture from penetrating the cartridge case. In the blank cartridge according to the invention, the required mass and position of the centre of gravity can be adjusted due to a variable depth and/or size of cross-section of the blind bores starting from the connecting plane in the projectile part and cartridge case. Thus, the blind bores always start from the separating point of the two parts. The projectile part and cartridge case may be formed from steel or from the material used for live ammunition.

Basically, the projectile part and the cartridge case are produced from a material used for the corresponding components of the live cartridge, with corresponding properties of strength and hardness, in which case even the facilitated machinability and careful treatment of the weapons play a part in the selection of the material.

One example of the invention is illustrated in the drawings, in which: Figure 1 shows a blank cartridge partly in section, Figure 2 shows the parts of of the cartridge screwed together according to the detail II in figure 1, but in the unscrewed state.

In the blank cartridge illustrated in figure 1, the reference numeral 1 designates the projectile part and 2 the cartridge case. In the cartridge case 2, blind bores located opposite each other on the periphery are provided as marking bores 3. At this point the blind bores 3 prevent the penetration of foreign bodies and moisture into the inside of the blank cartridge.

At its cylindrical end, the projectile part 1 comprises a shoulder 4 of reduced diameter, which comprises an external screwthread 5. The cartridge is provided with a corresponding internal screwthread 6 at its end adjacent the projectile part 1. In order to prevent an accidental loosening of the screw connection, an adhesive 7 is applied to the screwthreads 5 and 6 screwed one to the other. Further marking paint is applied at 8, whereas the entire outer surface is coated with a lacquer 9 for outdoor use. The blind bore 10 in the projectile part 1 and the blind bore 11 in the cartridge case, which both start from the connecting plane of the blank cartridge, are adapted as regards their depth and their crosssection to the required total mass of the cartridge and the required position 12 of the centre of gravity.

The projectile part 1 and the cartridge case 2 are two simple turned parts made from steel, which are connected to each other in a simple manner by screwing and secured by adhesive.

Due to the position of the separating point on an outer contour 1 3 of the blank cartridge, the connecting seam is not visible from outside.

Claims (8)

1. Blank cartridge for fire-arms, in particular for automatic machine guns, with a projectile part and a cartridge case connected to the latter, characterised by the screwing of the projectile part to the cartridge case at their separating point, which is located at places where the diameter is reduced, transition points of the diameter or on peripheral edges or recesses in the outer contour of the blank cartridge.

2. Blank cartridge according to claim 1, wherein the external screwthread provided on the cylindrical end of the projectile part comprises a shoulder whereof the diameter is reduced to such an extent that the cartridge case screwed to its internal screwthread has the same outer diameter as the outer diameter of the projectile part.

3. Blank cartridge according to claims 1 and 2, wherein the screwthreads screwed one to the other are secured with an adhesive.

4. Blank cartridge according to claims 1 and 2, wherein the marking bores provided in the cartridge case on the outer periphery are blind bores.

5. Blank cartridge according to any one of the preceding claims, wherein the required mass and position of the centre of gravity of the blank cartridge can be adjusted due to a variable depth and/or size of cross-section of the blind bores in the projectile part and the cartridge case starting from the connecting plane.

6. Blank cartridge according to any one of claims 1 to 5, wherein the projectile part and the cartridge case are formed from the material used for the live cartridge.

7. Blank cartridge according to any one of claims 1 to 5, wherein the projectile part and the cartridge case are made from steel.

8. A blank cartridge for fire-arms, substantially as herein described with reference to the accompanying drawings.