BOTTLENECK AMMUNITION WITH HIGH MUZZLE VELOCITY

Abstract: The invention relates to ammunition suitable for firing from a side arm comprising a cartridge adapted to fire a projectile (6), the cartridge case (1) having at one end a portion (3) of reduced diameter, i.e. a bottleneck cartridge, the projectile (6) being held in the said portion (3) of reduced diameter (D), wherein the ratio of the external diameter (B) of the cartridge case (1) at its widest point to the external diameter of the projectile (6) at its widest point is such that when the projectile (6) is fired into a target, high velocity wounding is caused. The invention also relates to a gun barrel (10) through which the ammunition can be shot, and a gun comprising such a barrel. The projectile (6) has a diameter of 5.56 mm (0.224 inch). The length of the cartridge case (1) lies between 17 and 25 mm, its maximum diameter at about 9-12 mm. The cartridge case may be made from a 0.40 Smith and Wesson (S & W) cartridge case.

Description: BOTTLENECK AMMUNITION WITH HIGH MUZZLE VELOCITY Field of the invention The invention relates to firearms, and in particular to improved ammunition for side arms and improved side arms to fire such ammunition. Background to the Invention There is a need for an ammunition capable of being fired from a side arm which has high muzzle velocity, great penetrative power and excellent accuracy. None of these characteristics is found in present ammunition types suitable for firing from a side arm. The need is particularly great in police forces and special forces. Body armour which is currently available makes most side arms ineffective. However, in many cases a rifle, which would provide the penetrative power necessary is not suitable, simply because it cannot be drawn quickly enough, or concealed. It is well understood by those skilled in the art of weaponry that firearms fall into four separate families, those being: a) Small calibre weapons using ammunition ranging in size from 0.22 inch which are commonly fired from small handguns; b) Small arms weapons which use straight sided centre fire ammunition, the ammunition being fired from handguns and semi-automatic guns, the common bores being 0.38 inch, 0.357 inch, 0.44 inch, 9 mm and 10 mm which offer accuracy over a range up to 50 metres; c) Combat rifles which fire ammunition sending projectiles at very high velocities over ranges of 500 metres plus, the common bores being 0.223 inch (5.56 mm), 5.7 mm, 0.303 inch, 7.62 mm and 0.50 inch; and d) Heavy weapons for firing ammunition up to 2 kilometres commonly having bores of 20 mm, 30 mm and larger, and which are used in extreme range combat to deliver large payloads, e.g. anti-tank and anti-aircraft ammunition. Small arms and small calibre weapons are convenient simply because they are small and lightweight, which makes them easy to use and carry about the person. However, the performance of these types of weapon is limited. They cannot fire projectiles over long distances, and furthermore are very inaccurate at anything more than short distances. In general, pistol ammunitions have projectiles of a diameter which corresponds to the internal diameter of the cartridge case, the walls of the cartridge case being parallel, whereas rifle ammunitions have projectiles significantly smaller in diameter than the cartridge cases to which they are attached. The result is a projectile which travels further and is more accurate. The types of wound produced by standard pistol and rifle ammunitions are quite different. Pistol ammunition produces low velocity wound characteristics, characterised in animals by the destruction of tissue in the path of the projectile, and a minor amount of secondary cavity damage around the path of the projectile. It is the effect of the projectile destroying objects in its path which neutralises the target. On the other hand, rifle ammunition produces high velocity wounding where it is not only destruction of tissue by the projectile which causes neutralisation, but damage to tissues caused by a velocity induced shock wave. The projectile itself causes limited damage, rather it is the shock wave induced by the projectile which results in severe trauma damage, sometimes known as temporary cavity damage. Single shot pistols, often being of bolt action type have been adapted to receive a rifle cartridge. However, it would be desirable to produce ammunition suitable for a standard side arm capable of producing high velocity wounding in a target. Many attempts have been made to optimise the performance of small arms and small calibre weapons. Each time the result has been a larger weapon. For example the Calico made by Calico Arms, and the P90 made by FN. Although both of these weapons increase the accuracy and distance of the projectile fired, neither is suitable for single handed use. The only known ammunition for use in side arms which utilised a projectile of smaller diameter than the internal diameter of the cartridge case to which it was attached was the Mauser Parabellam, which consisted of a projectile having an external diameter of 7.65 mm attached to a case having an external diameter of 9.6 mm. Whilst improved velocity and penetrative capacity were noted, this ammunition still produced low velocity wound characteristics. Many of the improved weapons also suffer problems in their re-arranged feed mechanisms and magazines. The constraints of a small automatic or semi-automatic weapon mean that a small compact ammunition having a short case length are required. Assuming that the weapon is to provide a reasonable number of shots then the ammunition will generate a low velocity, have drastically reduced terminal effects, and produce problems with terminal effects as a result of its small size. The problem in controlling the burn characteristics of the powder in cartridge cases suitable for use in automatic or semi-automatic side arms have lead those skilled in the art to develop ammunition having parallel sides. However, there is a need for police officers to be provided with side arms having penetrative power greater than that which can presently be provided. There is a limit velocity above which a projectile of a given diameter will cause a high velocity wound. It would therefore be desirable to provide ammunition capable of being fired from a side arm which has a longer range and gives greater accuracy than currently available ammunition. It would also be desirable to provide a side arm suitable for, or to modify parts of existing side arms to make them capable of, firing such ammunition. It would be advantageous to be able to utilise commonly available projectiles. It would also be advantageous to be able to utilise commonly available cartridge cases. Furthermore, it would be desirable to provide ammunition for a self-loading, automatic, or semi-automatic side arm capable of firing the projectile at a velocity in excess of the limit velocity for the said projectile. The term sidearm shall be understood to encompass weapons such as pistols, and carbines. Summary of the Invention The invention provides ammunition suitable for firing from a side arm comprising a cartridge adapted to fire a projectile, the cartridge case having at one end a portion of reduced diameter, the projectile being held in the said portion of reduced diameter, wherein the ratio of the external diameter of the cartridge case at its widest point to the external diameter of the projectile at its widest point is greater than 1.26 to 1. One aspect of the invention provides ammunition suitable for firing from a side arm comprising a cartridge adapted to fire a projectile, the cartridge case having at one end a portion of reduced diameter, the projectile being held in the said portion of reduced diameter, wherein the ratio of the external diameter of the cartridge case at its widest point to the external diameter of the projectile at its widest point is such that when the projectile is fired into a target high velocity wounding is caused. The invention also provides a cartridge case having at one end a portion of reduced diameter to receive a projectile therein, wherein the ratio of the external diameter of the cartridge case at its widest point to the internal diameter of the portion of reduced diameter at its widest point is greater than 1.26 to 1 , and is preferably between 1.5 to 1 and 2.8 to 1 , and still more preferably is 1.3 to 1 and 2.0 to 1. Preferably, the ratio of the external diameter of the cartridge case at its widest point to the external diameter of the projectile at its widest point is between 1.5 to 1 and 2.8 to 1. Preferably, the external diameter of the cartridge case at its widest point is 1.3 to 2.0 times the external diameter of the projectile. Even more preferably, the external diameter of the cartridge case at its widest point is substantially .8 times the external diameter of the projectile. Still more preferably, the external diameter of the projectile is substantially 5.56 mm, and the external diameter of the cartridge case is substantially 10.80 mm. Advantageously, the cartridge case is formed from a standard parallel sided cartridge case, having a length of between 17 and 25 mm. The projectile may be a standard 5.56 mm (0.224 inch) projectile. The cartridge may be formed from a standard 10 mm cartridge case, having a length of 25 mm. The cartridge may be formed from a standard 40 Smith & Wesson parallel sided cartridge case, having a length of 21.5 mm. The cartridge case may be a high pressure or low pressure case. In another embodiment of the invention, the external diameter of the cartridge case is substantially 9.6 mm and the external diameter of the projectile is greater than or equal to 4.5 mm and less than or equal to 6 mm. In another aspect of the invention the external diameter of the cartridge case is substantially 12 mm and the external diameter of the projectile is greater than or equal to 4.5 mm and less than or equal to 6 mm. The cartridge case may be swaged to provide the portion of reduced diameter. The cartridge case is preferably formed from brass. The projectile may be a standard full metal jacketed projectile. The powder used in the cartridge is preferably a nitro based powder. One aspect of the invention also provides a gun barrel having a chamber at one end so shaped and dimensioned as to receive ammunition according to the invention, one end of the said chamber entering into a rifled barrel of a diameter corresponding to the diameter of the projectile to be shot therethrough. Another aspect of the invention provides a self-loading, automatic, or semiautomatic side-arm comprising a gun barrel having a chamber at one end so shaped and dimensioned as to receive ammunition according to the invention, one end of the said chamber entering into a rifled barrel of a diameter corresponding to the diameter of the projectile to be shot therethrough. The ammunition of the invention fires its projectile at a much greater velocity, and therefore over a much longer range than would be the case with ammunition attached to a straight sided cartridge case. This is because the diameter of the projectile is less than the diameter of the case. The ammunition of the invention allows side arms to fire projectiles which behave in a similar manner to projectiles fired from rifles. The projectiles fired from ammunition according to the invention can produce high velocity wounding. The ammunition uses known components which are the subject of considerable research regarding flight characteristics and terminal effects. Existing side arms can easily be modified to use the ammunition of the invention by the replacement of a standard barrel with a barrel according to the invention. Brief description of the Drawings In the drawings which illustrate exemplary embodiments of the invention: Figure 1 is a side view of a cartridge case comprising part of ammunition according to the invention; Figure 2 is a cross-section of a cartridge case comprising part of ammunition according to the invention; and Figure 3 is a cross-section of ammunition according to the invention; Figure 4 is a cross-section of a barrel according to another aspect of the invention; Figure 5 is a graph of bullet velocity against distance for the ammunition of the invention and two other ammunition types of the art; Figure 6 is a graph of bullet energy against distance for the ammunition of the invention and two other ammunition types of the art; Figure 7 is a graph of bullet drop against distance for the ammunition of the invention and two other ammunition types of the art; Figure 8 is a graph of time of flight against distance for the ammunition of the invention and two other ammunition types of the art; Figure 9 is a graph of bullet path against distance for the ammunition of the invention and two other ammunition types of the art; and Figure 10 is a graph of combined distance from center against distance for the ammunition of the invention and two other ammunition types of the art. Detailed Description of the Preferred Embodiments Figure 1 shows a cartridge case 1 having a primer 2 attached to one end thereof. At the other end of the case 1 there is a portion of reduced diameter 3. In the region 4 between the straight sided portion of the cartridge case 1 and the portion of reduced diameter 3, the sides of the cartridge case slope. In the preferred embodiment the diameters A and B are 10.80 mm, the diameter C is 10.75 mm, the diameter D of the portion of reduced diameter 3 is 6.46 mm, and the internal diameter E is 5.66 mm. Letters F to K designate lengths of different parts of the cartridge case 1. In the preferred embodiment K is 23.00 mm, J is 19.25 mm, I is 15.82 mm, H is 3.20 mm, G is 2.48 mm and F is 1.40 mm. The angle y is 32 degrees in the preferred embodiment. The cartridge case 1 is formed by taking a standard 25 mm cartridge case and forming the portion of reduced diameter and the region having sloping sides by means of swaging. The internal diameter E of 5.66 mm accommodates a standard 0.224 inch (5.56 mm) projectile. The cartridge case 1 is shown in cross-section in Figures 2 and 3, and it can be seen that the case 1 has an internal chamber 5 in which powder is held. As can be seen from Figure 3, a projectile 6 is fitted in the portion of reduced diameter 3. As the powder (not shown) held in the internal chamber 5 burns energy is released, and so the projectile is forced out of the cartridge case 1. The projectile 6 comprises an inner shaped steel or lead mass 8, surrounded by a copper jacket 7. Many different projectiles of a size suitable to fit into the portion of reduced diameter 3 are known and may be used in place of the projectile 6 shown. In Figure 4 there is shown a barrel 10, comprising at one end a chamber 11 which is shaped to accommodate ammunition according to the invention, and a rifled barrel section 12. The barrel 10 is attached to a weapon by means of block 13 having an aperture 14 through which a pin may pass. The chamber 11 has a sloping face 15 and a portion of reduced diameter 16 which co-operate with the sloping face 4 and portion of reduced diameter 3 of the cartridge case shown in Figures 1 and 2. In the barrel 10, beyond the portion of reduced diameter 16, the diameter of chamber 1 1 tapers 17 for a short distance to the end of the chamber 11. At the end of the chamber 1 1 , the rifled barrel section 12 begins. Tapered section 17 accommodates the shaped projectile such as the projectile 6 shown in Figure 3. The dimensions of the chamber may be nominally 0.1 mm greater than those of the ammunition according to the invention. Figures 5 to 10 are graphs showing the performance of the ammunition of the present invention compared with the performance of 9mm FMJ and 0.40 Smith and Wesson as modelled on the "Oehler Ballistic Explorer". In each graph, trace 1 indicates the performance of the ammunition of the invention, trace 2 indicates the performance of 9mm FMJ ammunition, and trace 3 indicates the performance of 0.40mm Smith and Wesson ammunition. Each of the graphs serves to show that the ammunition of the invention significantly out performs the 9mm FMJ and the 0.40 Smith and Wesson.

Claims: Claims 1. Ammunition suitable for firing from a side arm comprising a cartridge adapted to fire a projectile, the cartridge case having at one end a portion of reduced diameter, the projectile being held in the said portion of reduced diameter, wherein the ratio of the external diameter of the cartridge case at its widest point to the external diameter of the projectile at its widest point is such that when the projectile is fired into a target high velocity wounding is caused. 2. Ammunition according to Claim 1 , wherein the ratio of the external diameter of the cartridge case at its widest point to the external diameter of the projectile at its widest point is greater than .26 to 1. 3. Ammunition according to Claim 2, wherein the ratio of external diameter of the cartridge case at its widest point to the external diameter of the projectile at its widest point is between 1.5 to 1 and 2.8 to 1. 4. Ammunition according to Claim 2, wherein the ratio of external diameter of the cartridge case at its widest point to the external diameter of the projectile at its widest point is between 1.3 to 1 and 2.0 to 1. 5. Ammunition according to Claim 3 or 4, wherein the external diameter of the cartridge case at its widest point is substantially 1.8 times the external diameter of the projectile. 6. Ammunition according to Claim 1 , wherein the ratio of the external diameter of the cartridge case at its widest point to the internal diameter of the portion of reduced diameter at its widest point greater than 1.26 to 1. 7. Ammunition according to Claim 6, wherein the ratio of the external diameter of the cartridge case at its widest point to the internal diameter of the portion of reduced diameter at its widest point is between 1.5 to 1 and 2.8 to 1. 8. Ammunition according to Claim 6, wherein the ratio of the external diameter of the cartridge case at its widest point to the internal diameter of the portion of reduced diameter at its widest point is between is 1.3 to 2.0. 9. Ammunition according to Claim 1 , wherein the external diameter of the projectile is substantially 5.56 mm, and the external diameter of the cartridge case is substantially 10.80 mm at its widest point. 10. Ammunition according to any of Claims 1 to 8, wherein the cartridge case is formed from a standard parallel sided cartridge case, having a length of between 17 and 25 mm. 11. Ammunition according to any of Claims 1 to 8, wherein the projectile is a standard 5.56 mm (0.224 inch) projectile. 12. Ammunition according to any of Claims 1 8, wherein the cartridge is formed from a standard 10 mm cartridge case, having a length of 25 mm. 13. Ammunition according to Claim 1 , wherein the cartridge is formed from a standard 40 Smith & Wesson parallel sided cartridge case, having a length of 21.5 mm. 14. Ammunition according to any preceding claim, wherein the cartridge case is a high pressure case. 15. Ammunition according to Claim 1 , wherein the external diameter of the cartridge case is substantially 9.6 mm and the external diameter of the projectile is not less than to 4.5 mm and not greater than 6 mm. 16. Ammunition according to Claim 1, wherein the external diameter of the cartridge case is substantially 12 mm and the external diameter of the projectile is not less than 4.5 mm and not greater than 6 mm. 17. Ammunition according to any preceding claim, wherein the cartridge case is swaged to provide the portion of reduced diameter. 18. Ammunition according to any preceding claim, wherein the cartridge case is formed from brass. 19. Ammunition according to any preceding claim, wherein the projectile is a standard full metal jacketed projectile. 20. A gun barrel suitable for a side arm having a chamber at one end so shaped and dimensioned as to receive ammunition according to any of claims 1 to 19. 21. A sidearm comprising a gun barrel having a chamber at one end so shaped and dimensioned as to receive ammunition according to any one of Claims 1 to 19. 22. Ammunition suitable for firing from a side arm substantially as described with reference to, or as shown in, Figures 1 to 3. 23. A gun barrel suitable for a side arm substantially as described with reference to, or as shown in, Figure 4.

Inventors: ALEXANDER WILLIAM ROGERS HENRY, BARRACLOUGH TREVOR JOE, ALEXANDER, WILLIAM, ROGERS, HENRY, BARRACLOUGH, TREVOR, JOE
Applicants: ALEXANDER WILLIAM ROGERS HENRY, BARRACLOUGH TREVOR JOE, BAUER ERAN NICODEMUS, BAUER GERARD MIET, ALEXANDER, WILLIAM, ROGERS, HENRY, BARRACLOUGH, TREVOR, JOE, BAUER, ERAN, NICODEMUS, BAUER, GERARD, MIET
Application year: 1997
Main classification: F42B5
IPC codes: F41A21, F41C3, F42B5