GB2338283A

GB2338283A - A cartridge

Info

Publication number: GB2338283A
Application number: GB9812659A
Authority: GB
Inventors: Kong Chan
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-06-11
Filing date: 1998-06-11
Publication date: 1999-12-15
Also published as: GB9812659D0

Abstract

Cartridge including a generally hollow chamber (12,22,32) containing gunpowder (4) and a weighted nose portion (11,21,31). A firing cap (13,23,33) is removably attached to the chamber (12,22,32). In use, firing of the cap (13,23,33) causes explosion of the gunpowder (4) so the chamber (12,22,32) including the nose portion (11,21,31) are separated from the firing cap (13,23,33) and are projected from a gun in which the cartridge is provided. Accordingly, additional material in the form of the chamber (12,22,32) is fired from the gun compared to known cartridges.

Description

1 BULLET 2338283 A conventional cartridge comprises a bullet which is

generally solid and made of a heavy material, typically metal, which is joined to a hollow chamber within which gunpowder is provided. The end opposite the bullet is closed, and includes a firing cap provided to ignite the gunpowder. The cartridge is positioned in the chamber of the gun so that the bullet at the front is located within the barrel of the gun and the hollow chamber of the cartridge is positioned within the chamber of the gun. By striking the firing cap with the firing pin of the gun, the gunpowder in the chamber of the cartridge is exploded causing the bullet to separate from the chamber of the cartridge and be projected along the barrel of the gun. The empty cartridge chamber and firing cap remain in the gun and are removed manually or by a mechanical ejections system before another cartridge is loaded into the gun.

As the bullet passes through the barrel of the gun, some material may be removed from the barrel and may cause some deformation of the barrel, for example as the bullet contacts the riffling provided on the inside of the barrel to cause rotation of the bullet in flight. This removal of material may result in compressed gas caused by the explosion of the gunpowder which drives the bullet from the gun to pass the bullet, thereby reducing the speed at which the bullet is projected from the gun and the rotation of the bullet, or causing the bullet to move off its axial alignment within the barrel.

Further, the loss of material from the inside of the barrel may eventually lead to the failure of the barrel. Additionally, due to the high speed of the bullet within the barrel while contacting the barrel and removing material from the inner surface of the barrel, the barrel will become hot. This can lead to distortion of the 2 barrel, and the high temperature may cause the explosion of the gunpowder in a cartridge before the firing of the gun.

According to the present invention, a cartridge comprises a generally hollow chamber containing gunpowder and having a weighted nose portion, and a firing cap removably attached to the chamber and arranged so that, in use, the explosion of the gunpowder within the chamber causes the chamber including the nose portion to separate from the firing cap and be projected through the barrel of a gun in which the cartridge is provided.

is In the present invention, the bullet shot from the gun comprises a substantial part of the cartridge chamber, including both the solid weighted nose portion and the casing which held the gunpowder initially. This is advantageous as additional material is shot from the gun making the bullet more effective, but no additional material is required to make the cartridge as the additional material shot is that forming the gunpowder containing chamber. Accordingly, more effective use is made of the material forming the cartridge.

As the length of the bullet according to the present invention is longer than conventional bullets, it is possible to provide any desired amount of heavy material in the nose portion to give a bullet of any desired weight without increasing the size of the cartridge. The additional length of the bullet is also advantageous in improving the accuracy of the bullet and increasing the speed of the bullet and thereby increasing the distance over which the bullet can be shot. The additional length of the bullet helps keep the bullet stable and prevents this from wobbling both in the barrel 3 of the gun and in the air after the bullet leaves the gun.

It is preferred that the nose portion of the cartridge is formed integrally with the chamber of the cartridge. In this case the nose portion may be an extension of the side walls of the chamber, and the nose portion may be filled with a heavy material, for example lead, to give the required weight.

The nose portion of the cartridge may include an explosive which may detonate on impact with the target, a guidance system or other material or equipment.

Preferably that cartridge chamber is formed of metal, although other material, for example plastics, can also be used. The side walls of the cartridge chamber are formed preferably of a thin material. This is advantageous as the force of the explosion will cause the thin side walls to be forced outwardly to maintain close proximity with the internal bore of the barrel of the gun. This ensures that the highly compressed gas in the barrel due to the explosion of the gunpowder cannot pass around the bullet, and therefore all the force due to the explosion of the gunpowder acts to drive the bullet from the gun. This results in the bullet having a greater speed and increased range. Due to the easy deformability of the side walls of the chamber of the cartridge, there will only be relatively light contact between the side walls and the inner surface of the barrel of the gun, and therefore there will be minimal wearing of the material of the barrel, thereby increasing the life of the barrel. This light contact also reduces the heat produced by the passage of the bullet through the barrel of the gun. Preferably the outer surface of the side walls are made of a soft material to further reduce damage to the 1 4 barrel. it is preferred that the weighted nose portion, which will be more rigid than the side wall has a diameter less than that of the bore so this portion does not contact the bore. This increases the life of the barrel.

Preferably the firing cap is less than half the overall length of the cartridge, and more preferably is less than a quarter of the length of the cartridge.

The greater proportion of the cartridge which is fired from the gun, the more effective the bullet and the less material remains in the gun unused.

is To achieve a good seal between the cap and the cartridge chamber, it is preferred that the chamber surround an outer peripheral surface of the cap to form an interference fit. By providing the cartridge chamber around the outside of a surface of the cap, for example around a projection or flange, a better seal is achieved and the diameter of the cartridge chamber is greater than where this fits inside a rim of the cap. Advantageously, the cap may be provided within the cartridge chamber. In this case, when the gunpowder within the cartridge chamber is exploded, the cap is blown out of the cartridge chamber, and the casing is projected through the barrel of the gun. As the bullet leaves the barrel of the gun, there will be a sudden rush of compressed gas out of the end of the barrel, and this will suck the cap behind the bullet and automatically discharge this through the end of the barrel. Therefore there is no need to empty the chamber of the gun manually after firing or to provide a mechanical ejection system allowing simplification of the gun and giving improved operation and safety. In this case, it is preferred that none of the dimensions of the cap are greater than the diameter of the bore of the barrel so that the cap can pass easily through the barrel even if this is rotated during its passage through the barrel. It is important that the cap does not become jammed in the barrel as this would cause the barrel to explode when another bullet is fired and the bullet cannot pass along the barrel due to a jammed cap.

It is preferred that the chamber of the cartridge is slightly tapered, including a portion having a diameter slightly larger than the diameter of the barrel. In this way, the cartridge is not able to fall out of the barrel by gravity alone, but when the gunpowder is exploded, the force is sufficient to deform the cartridge chamber and allow this to pass through the barrel. Further, this ensures that the cartridge is held in place whilst it is struck by the firing pin, since movement of the cartridge when it is struck may prevent the primer firing. The cartridge chamber may have an outer diameter which increases gradually along its length, with the rear having a larger diameter than the tip, but preferably the cartridge is generally rounded along its length with a portion of larger diameter between the ends of the cartridge. This gives a bullet having improved aerodynamic properties, and therefore one which travels through the air more efficiently.

The cartridge may have a circular crosssection, or may be of a different shape, for example triangular. It is preferred that the internal bore of the barrel of the gun has a shape corresponding to that of the cartridge.

The cap may be struck by the firing pin of the gun, or may have an electronic ignition to explode the gunpowder.

6 As the chamber of the cartridge must pass is through the barrel of the gun, this has to be of a smaller size than a corresponding conventional cartridge for a particular gun, since a normal cartridge is of a size larger than that of the barrel to retain the cartridge within the chamber of the gun. Accordingly it is advantageous for the chamber of the gun to be provided with a reduced diameter compared to a conventional chamber so that the chamber is of approximately the same size as the barrel of the gun. This can be achieved by providing an insert within the chamber of a conventional gun, the insert having an internal diameter corresponding to the diameter of the barrel of the gun to act as an extension to the barrel. Alternatively, the conventional gun can be modified by providing a new chamber which has an internal diameter generally the same as that of the barrel of the gun to act as an extension to the barrel.

Yet further, the gun may be designed in which no chamber of increased diameter is provided. In any case, the chamber preferably includes riffling corresponding to that of the barrel. The effect of providing a chamber which has substantially the same diameter bore as the barrel of the gun, especially where the chamber includes riffling, is that this improves the accuracy of the gun since the flight of the bullet is stabilized by the barrel for a longer distance than where the chamber of the gun does not form an extension of the barrel.

Rather than a single gun chamber, a rotatable member including a number of spaced parallel chambers may be provided. In this case, each of the chambers may be loaded with a cartridge, and the member rotated to align one of these with the barrel of the gun. When the bullet has been fired from the chamber, the member is rotated to align another cartridge with the barrel of the gun.

7 The cartridge of the present invention can be used in guns of any size, including pistols, riffles, canons.

Examples of the present invention and the prior art will be described and contrasted with reference to the accompanying drawings, in which:

Figure 1 shows a cross-section of a conventional cartridge for a gun; Figures 2 to 4 show cross-sections through examples of bullets according to the present invention; 15 and, Figure 5 shows a cross-section through a chamber and part of a barrel of a gun including the bullet shown in Figure 2.

As shown in Figure 1, a conventional cartridge comprises a bullet 1 made of heavy material. Typically this comprises a metal shell filled with lead or other relatively heavy material. A cartridge chamber 2 is filled with gunpowder 4. A priming cap 5 is provided in an end cap 3 at the end of the chamber 2. In use, the cartridge is positioned within a gun with the bullet 1 in the barrel of the gun with the remainder of the cartridge held in the chamber of the gun, supported from behind by the breech block. When the gun is cocked and the trigger pulled, the hammer contacts the firing pin which strikes the priming cap 5 to cause the explosion of the gunpowder 4 within the chamber 2 of the cartridge. The gases produced by the explosion of gunpowder 4 cause the bullet 1 to be forcibly separated from the chamber 2 of the cartridge and propelled through the barrel of the gun. The empty chamber 2 and the end cap 3 including the 8 primer cap 5 remain in the gun, and the bolt of the gun must be retracted to allow for the removal of the spent cartridge and for a new cartridge to be inserted into the chamber of the gun.

is Figure 2 shows a first example of the present invention in which the cartridge includes a chamber defined by a generally tubular side wall 12 for containing gunpowder 4, the side wall 12 being attached or integrally formed with the head 11. In the example shown in Figure 2, the head 11 is formed as an extension of the side wall 12 and is filled with a lead to weight the nose portion of the cartridge. The side wall 12 is slightly tapered, having an increasing diameter further from the head. An end cap 13 is provided to close the gunpowder chamber. The cap 13 includes a priming cap 15. The side walls 12 of the chamber fit around an outside projection of the cap 13. The head 11 of the cartridge chamber is generally solid.

The cartridge according to the present invention is used in a modified or specially designed gun in which the normal enlarged diameter chamber of the gun is replaced by a chamber having the same diameter as the bore of the barrel of the gun. As shown in Figure 5, the gun includes a barrel 14 and an enlarged chamber 15. The enlarged chamber 15 is conventionally provided to hold the chamber of the cartridge within the gun as the bullet is discharged along the barrel 14 of the gun. In the modification required to shoot the bullet according to the present invention, an insert 16 is provided within the chamber 15, the internal diameter of the insert 16 being generally similar to that of the barrel 14 of the gun. The inner diameter of the insert 16 includes riffling corresponding to that on the inside of the barrel 14. Rather than provide a separate insert 9 is 16 within the chamber 15 of the gun, the chamber 15 may be replaced with a chamber having the required diameter through bore, or a gun may be provided in which there is no separate chamber of enlarged diameter provided.

The end cap 13 includes an enlarged annular rib which is held by a projection (now shown) in the chamber 16.

The gunpowder 4 within the chamber is ignited in any conventional manner, for example by striking the cap 15 with a firing pin or by an electrically generated spark. The explosion of the gunpowder 4 causes the generation of gas which causes the chamber 12 of the cartridge and the head 11 to separate from the cap 13 and be propelled through the barrel 14 and fired from the gun. The cap 13 remains within the chamber 15.

Due to the high pressure generated within the barrel of the gun, the side walls 12 of the cartridge will be forced outwardly and into contact with the inner wall of the barrel 14 and insert 16. This ensures that no gas can escape around the bullet as it passes along the barrel 14 of the gun and ensures contact with the riffling. The riffling on the inside of the barrel 14 and insert 16 imparts axial rotation to the bullet as it passes along the length of the barrel 14 and insert 16. After the bullet leaves the end of the barrel 14, the heavy head 11 of the bullet causes the bullet to fly quickly and accurately to its target. The side walls 12 attached to or formed integrally with the back of the head 11 of the bullet assist in the accurate flight of the bullet. When the bullet strikes the target, the side walls 12 behind the head 11 increase the effectiveness of the bullet.

A second example of a cartridge according to the present invention is shown in Figure 3. In this example, the cap 23 is provided within the side walls 22 of the cartridge. The cartridge is provided within a gun in the same way as the first example. The cap 23 includes a projection which extends outside the chamber of the cartridge, and which includes two annular ribs 24,26 having an annular recess 27 between. The outer diameter and the length of the cap 23 are both less than the internal dimension of the barrel to ensure that the cap 23 can pass through the barrel irrespective of its orientation. The cap 23 includes a primer cap 25. When the primer cap 25 is struck by the firing pin within the gun, or the charge is ignited in any other way, the gunpowder 4 within the cartridge explodes causing the side walls 22 of the cartridge and the head 21 to be propelled along the barrel 14 of the gun towards the target. The cap 23 which is left behind is smaller than the inner diameter of the barrel 14 of the gun. As soon as the bullet passes out of the end of the barrel, the compressed gas in the barrel is exhausted to the atmosphere and therefore there will be a rush of gas from inside the barrel. This draws the cap 23 through the barrel 14, thereby automatically clearing the barrel 14 and insert 16 of the gun ready for the next cartridge.

A third preferred example of a cartridge according to the present invention is shown in Figure 4.

This example is generally similar to the second example except the side walls 32 of the chamber are curved along their length so the cartridge has a largest diameter intermediate the ends of the cartridge. The front end of the cartridge includes a portion of increased weight 31, for example by lead provided at the tip of the cartridge. In this example, the cap 33 is provided within the side walls 32 of the cartridge. A flange is provided to 11 prevent the cap 33 being pushed inside the cartridge chamber. The cartridge is held within the chamber of the gun by the two annular ribs 34,35 provided on the outside of the side walls 32. These ribs 34,35 are engaged by a projection in the barrel of the gun. The ribs 34,35 also help to maintain the axial alignment of the cartridge with the barrel 14 of the gun and ensure there is no gap around the outside of the cartridge as it passes along the barrel 14 which would allow the gas from the explosion of the gunpowder to pass around the bullet as it is fired.

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Claims

CLAIMS:

1. A cartridge comprising a generally hollow chamber containing gunpowder and having a weighted nose portion, and a firing cap removably attached to the chamber arranged so that, in use, the explosion of the gunpowder within the chamber causes the chamber including the nose portion to separate from the firing cap and be projected through the barrel of a gun in which the cartridge is provided.

2. A cartridge according to Claim 1, in which the chamber is formed of metal.

3. A cartridge according to Claim 1, in which the chamber is formed of plastics.

4. A cartridge according to any preceding Claim, in which the side walls of the chamber are formed of a thin material.

5. A cartridge according to any one of the preceding claims, in which the firing cap is less than half the overall length of the cartridge.

6. A cartridge according to Claim 5, in which the firing cap is less than a quarter of the length of the cartridge.

7. A cartridge according to any one of the preceding claims, in which the chamber surrounds an outer peripheral flange of the cap to form an interference fit.

8. A cartridge according to any one of the preceding claims, in which the cap may be provided within the chamber.

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9. A cartridge according to any one of the preceding claims, in which the largest dimension of the firing cap is less than the internal diameter of the barrel of the gun through which the cartridge is fired.

10. A cartridge according to any one of the preceding claims, in which the chamber is tapered along its length.

11. A cartridge according to Claim 10, in which the side walls are curved to give a portion of larger dimension between the ends of the chamber.

12. A cartridge according to any one of the preceding claims, in which the maximum diameter of the cartridge is slightly greater than the internal diameter of the barrel of the gun from which it is to be fired.

13. A cartridge according to any preceding claim in which the cartridge has a triangular cross-section perpendicular to its axis.

14. A gun for firing the cartridge according to any one of the preceding claims, in which the chamber of the gun has an internal diameter substantially the same as the barrel of the gun to operate as an extension of the barrel.

is. A gun according to Claim 14, in which the chamber of the gun includes a removable insert having an internal diameter substantially the same as that of the barrel.

16. A gun according to any one of Claims 13 or 15, in which the chamber of the gun includes riffling.

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17. A gun according to any one of Claims 14 to 16, in combination with a cartridge according to any one of Claims 1 to 13, in which, after firing, the cap and any other material in the barrel or chamber of the gun are automatically removed from the gun by the compressed gas leaving the barrel.