Patent Application
20250076011
This patent application claims priority to German Patent Application No. 10 2023 105 715.4, filed Mar. 8, 2023, which is incorporated herein by reference in its entirety.
The present disclosure relates to a jacket projectile, in particular a partial jacket projectile or an armor-piercing projectile (AP projectile), for ammunition with a caliber of less than, for example, 13 millimeters (mm), in particular less than 12.7 mm. Furthermore, the present disclosure relates to ammunition with such a jacket projectile.
Jacket projectiles are generally characterized by the fact that a projectile core, usually made of lead, is encased in a jacket of a harder metal alloy. The jacket thus protects the barrel of a firearm from the abrasion of the softer core and also prevents the softer core from deforming or even splintering when the projectile hits a target.
For environmental and health reasons, especially on practice shooting ranges, the use of lead as a material for projectiles is becoming increasingly unsuitable. When selecting materials for projectiles, there is therefore a conflict of interest, particularly between good precision and flight range and environmental compatibility. Alternative materials to lead, such as tin, zinc and copper, have proven to be less suitable due to their low density, which would ensure better environmental compatibility, but would result in significant losses in terms of precision and flight range. Furthermore, alternative solutions in the form of steel or brass full projectiles also have decisive disadvantages in terms of barrel service life and resistance to being pressed through the barrel of the firearm. This results in unfavorable internal ballistics. The pressure during powder combustion is too high while the resulting muzzle velocity is too low.
So-called armor-piercing projectiles (AP projectiles), also known as armor-penetrating or kinetic-energy projectiles, are generally used in military areas to penetrate and destroy armored and/or hardened faces of targets. The AP projectiles can have additives inside, such as explosives, to generate an additional effect after hitting a target, such as igniting the explosive.
A major challenge in the design of AP projectiles is that the core should form as large a part of the projectile as possible, wherein the projectile jacket is not primarily relevant to penetration. This means that the mass of the jacket should be kept as small as possible compared to the core.
Furthermore, when dimensioning the length-diameter, it must be considered that a core that is too long will guidingly be prone to breakage, while a core that is too short will have poorer penetration properties. The challenge with AP projectiles is therefore to find the optimum balance between barrel load, precision and penetration power.
WO 97/41404 A1 discloses a small-caliber AP projectile with a large, two-stage pointed tungsten carbide penetration core, which is enclosed in a guide and rests against the jacket on the pointed side. However, the projectile of WO 97/41404 A1 is not capable of satisfactorily solving the above-mentioned challenges.
An internal ballistic technical problem with AP projectiles, such as the one according to WO 97/41404 A1, is that the projectile is deformed as it is pressed through the barrel of the firearm. In addition, the considerable firing forces have an influence on the projectile geometry, which can result in uncontrolled and varying geometric changes to the projectile, which ultimately have a negative influence on the precision of the projectile.
The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate the embodiments of the present disclosure and, together with the description, further serve to explain the principles of the embodiments and to enable a person skilled in the pertinent art to make and use the embodiments.
The exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings. Elements, features and components that are identical, functionally identical and have the same effect are—insofar as is not stated otherwise—respectively provided with the same reference character.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present disclosure. However, it will be apparent to those skilled in the art that the embodiments, including structures, systems, and methods, may be practiced without these specific details. The description and representation herein are the common means used by those experienced or skilled in the art to most effectively convey the substance of their work to others skilled in the art. In other instances, well-known methods, procedures, and components have not been described in detail to avoid unnecessarily obscuring embodiments of the disclosure.
An object of the disclosure is to overcome the disadvantages of the prior art, in particular to provide a projectile with improved precision, wherein in particular its resistance to the forces associated with pressing the projectile through the barrel of the firearm is increased.
Accordingly, a jacket projectile, in particular a partial jacket projectile or an armor-piercing projectile (AP projectile), is provided for ammunition with a caliber of, for example, less than 13 mm, in particular less than 12.7 mm. AP projectiles form a special type of jacket projectile and are generally used in military areas to penetrate and destroy armored and/or hard faces of targets. They are also known as armor-piercing ammunition projectiles. Another special type of AP projectiles are armor-piercing incendiary projectiles (API projectiles) to which an additional flammable substance, for example zirconium, is added in order to produce an additional incendiary effect and/or arcing effect after penetrating the target, in particular its armor.
The jacket projectile according to the disclosure, also referred to as “projectile” for short, may comprise a core, a jacket, in particular tapering ogive-like in the direction of flight and surrounding the core, and a guide shoe arranged between the core and the jacket. The core can be pressed with the guide shoe and joined as a unit with the jacket, in particular pressed therewith, in order to form the final projectile. The jacket may comprise or consist of, for example, copper or alloys thereof, steel or other equivalent materials with regard to stability and press-through properties through the firearm barrel. Among other things, it is responsible for holding the hard core and the guide shoe of the core. In addition, the jacket incurs the internal and external ballistic functions of a normal projectile, as it can be easily formed into the required form and external shape. The guide shoe comprises or consists, for example, of steel or aluminum or alloys thereof. A modulus of elasticity of 50,000 N/mm2 to 250,000 N/mm2, a density value in the range of 2,500 kg/m3 to 8,000 kg/m3, a yield strength of at least 250 N/mm2 and/or an elongation at break of at least 5% have proven to be advantageous. The core, in particular the penetration core, may comprise or consist of hard material such as steel, sintered material, tungsten carbide, in particular containing tungsten or cobalt, in particular an alloy of 94% tungsten and 6% cobalt, tungsten carbide or hardened steel, in order to achieve the desired penetration performance of the projectile. Due to the high hardness of the core, it is virtually impossible to change its external shape after completion, so that manufacturing tolerances must be compensated for by the other parts of the projectile, in particular the guide shoe and the jacket. The front or outer end of the hard core sits more or less freely inside the ballistic jacket and only touches it in the portion of its circumferential shoulder. It also sits in the open part of the guide shoe. A modulus of elasticity of at least 500,000 N/mm2, in particular at least 550,000 N/mm2 or at least 600,000 N/mm2, a density value of at least 10,000 kg/m3, in particular at least 12,500 kg/m3 or 14,000 kg/m3 can be advantageous for the core. In other words, the jacket forms the outer shape of the projectile and accommodates the core consisting of a harder material as well as the guide shoe holding the core, which may, for example, be formed like a quiver and be open to the front in the direction of flight of the projectile in order to enable the core to be mounted in the shoe.
According to the first aspect of the present disclosure, the core is provided rear-sided with a profiling on its outer circumference, according to which the guide shoe is adapted in a shape-complementary manner in such a way that an anti-twist securing is formed between the guide shoe and the core. When in the present disclosure reference is made to nose or nose-sided, front or front-sided or rear or rear-sided, the corresponding designations are to be understood with regard to the direction of flight of the projectile or with regard to its orientation in the barrel of the firearm, wherein the projectile rear is arranged at the rear with respect to the direction of flight, i.e. rear-sided, and the projectile nose or projectile front is arranged at the front with respect to the direction of flight. The shape-complementary adaptation of the guide shoe to the core profiling can be produced in advance and/or first formed, in particular further developed, by joining, in particular pressing together, the guide shoe and core. The anti-twist securing between the guide shoe and core achieved in this way ensures that the twist resulting from firing the projectile is reliably transferred from the barrel to the core without causing relative twisting movements between the guide shoe and core, which has a negative effect on the precision of the projectile in particular. The anti-twist securing prevents the tendency of a projectile to deform during firing and/or pressing through the firearm barrel, particularly in an uncontrolled manner.
For example, the jacket has a hardness in the range of 45 HV to 120 HV, the guide shoe has a hardness in the range of 200 HV to 250 HV and/or the core has a higher hardness than the jacket, in particular a hardness of more than 920HV10 or 1200HV10.
According to an exemplary embodiment of the jacket projectile according to the disclosure, the profiling is provided circumferentially and/or has a cross, star or polygonal shape in cross-section, in particular a fully circumferential wave-like contour. In an exemplary further development, the profiling is formed as notch-free as possible and/or with a soft profiling transition, i.e. without sharp-edged transitions and/or profiling jumps along the profiling. It may be provided that the transitions along the profiling have as few and/or large radii as possible, such as in the range of 0.1 mm to 0.5 times the wall thickness of the projectile jacket.
In a further exemplary embodiment of the present disclosure, the profiling defines a profiling section on the core which is provided with at least one flattening, in particular a plurality of flattenings distributed at a particularly uniform distance in the circumferential direction, which has a different radial curvature with respect to a projectile center axis compared to a core section adjacent to the profiling section. The term “flattening” or “flattened” can be understood in relation to a curvature of the core shape, which in particular is basically formed in a cylindrical or conical shape, and/or in relation to the projectile center axis. For example, the profiling section can be inclined at an angle of 10° to 30°, such as in the range of 15° to 25°, relative to the projectile center axis. The individual flattenings can be formed identically and/or be directly adjacent to one another or be separated from one another by a particularly narrow cylindrical segment section which extends in the longitudinal direction of the projectile. It is clear that, according to the disclosure, the guide shoe is formed in a correspondingly shape-complementary manner on its inner circumference facing the profiling section, so that the anti-twist securing according to the disclosure is achieved, in particular in a form-fitting manner. According to a further aspect of the present disclosure, which can be combined with the preceding aspects and exemplary embodiments, a jacket projectile, in particular a partial jacket projectile or an armor-piercing projectile (AP projectile), is provided for ammunition with a caliber of, for example, less than 13 mm, in particular of less than 12.7 mm. AP projectiles form a special type of jacket projectile and are generally used in military areas to penetrate and destroy armored and/or hard faces of targets. They are also known as armor-piercing ammunition projectiles. Another special type of AP projectiles are armor-piercing incendiary projectiles (API projectiles) to which an additional flammable substance, for example zirconium, is added in order to produce an additional incendiary effect and/or arcing effect after penetrating the target, in particular its armor.
The jacket projectile according to the disclosure, also referred to as “projectile” for short, comprises a core, a jacket, in particular tapering ogive-like in the direction of flight and surrounding the core, and a guide shoe arranged between the core and the jacket. The core can be pressed with the guide shoe and joined as a unit with the jacket, in particular pressed therewith, in order to form the final projectile. The jacket comprises or consists of, for example, copper or alloys thereof, steel or other equivalent materials with regard to stability and press-through properties through the firearm barrel. Among other things, it is responsible for holding the hard core and the guide shoe of the core. In addition, the jacket incurs the internal and external ballistic functions of a normal projectile, as it can be easily formed into the required form and external shape. The guide shoe comprises or consists, for example, of steel or aluminum or alloys thereof. A modulus of elasticity of 50,000 N/mm2 to 250,000 N/mm2, a density value in the portion of 2,500 kg/m3 to 8,000 kg/m3, a yield strength of at least 250 N/mm2 and/or an elongation at break of at least 5% have proven to be advantageous. The core, in particular the penetration core, may comprise or consist of hard material such as steel, sintered material, tungsten carbide, in particular containing tungsten or cobalt, in particular an alloy of 94% tungsten and 6% cobalt, tungsten carbide or hardened steel, in order to achieve the desired penetration performance of the projectile. Due to the high hardness of the core, it is virtually impossible to change its external shape after completion, so that manufacturing tolerances must be compensated for by the other parts of the projectile, in particular the guide shoe and the jacket. The front or outer end of the hard core sits more or less freely inside the ballistic jacket and only touches it in the portion of its circumferential shoulder. It also sits in the open part of the guide shoe. A modulus of elasticity of at least 500,000 N/mm2, in particular at least 550,000 N/mm2 or at least 600,000 N/mm2, a density value of at least 10,000 kg/m3, in particular at least 12,500 kg/m3 or 14,000 kg/m3 can be advantageous for the core. In other words, the jacket forms the outer shape of the projectile and accommodates the core consisting of a harder material and the guide shoe holding the core, which can, for example, be formed like a quiver and be open at the front in the direction of flight of the projectile in order to enable the core to be mounted in the shoe.
According to a further aspect of the present disclosure, bottom faces of the core, jacket and guide shoe which lie on top of one another and are oriented transversely, in particular perpendicularly, to the longitudinal direction of the projectile are pressed against one another. It is clear that two pairs of pressing faces are each formed from two bottom faces facing each other, i.e. a core-guide shoe-pressing face pair and a guide shoe-jacket-pressing face pair. This double pressing of all three components against each other creates a particularly compact projectile rear, so that the precision of the projectile can be increased. The compact unit in the portion of the projectile rear also prevents relative movements, particularly in the direction of the longitudinal axis of the projectile, which have an uncontrolled and thus negative effect on the ballistics and thus the precision of the projectile.
According to a further aspect of the present disclosure, which can be combined with the preceding aspects and exemplary embodiments, a jacket projectile, in particular a partial jacket projectile or an armor-piercing projectile (AP projectile), is provided for ammunition with a caliber of, for example, less than 13 mm, in particular of less than 12.7 mm. AP projectiles form a special type of jacket projectile and are generally used in military areas to penetrate and destroy armored and/or hard faces of targets. They are also known as armor-piercing ammunition projectiles. Another special type of AP projectiles are armor-piercing incendiary projectiles (API projectiles) to which an additional flammable substance, for example zirconium, is added in order to produce an additional incendiary effect and/or arcing effect after penetrating the target, in particular its armor.
The jacket projectile according to the disclosure, also referred to as “projectile” for short, comprises a core, a jacket, in particular tapering ogive-like in the direction of flight and surrounding the core, and a guide shoe arranged between the core and the jacket. The core can be pressed with the guide shoe and joined as a unit with the jacket, in particular pressed therewith, in order to form the final projectile. The jacket comprises or consists of, for example, copper or alloys thereof, steel or other equivalent materials with regard to stability and press-through properties through the firearm barrel. Among other things, it is responsible for holding the hard core and the guide shoe of the core. In addition, the jacket assumes the internal and external ballistic functions of a normal projectile, as it can be easily formed into the required form and external shape. The guide shoe comprises or consists, for example, of steel or aluminum or alloys thereof. A modulus of elasticity of 50,000 N/mm2 to 250,000 N/mm2, a density value in the range of 2,500 kg/m3 to 8,000 kg/m3, a yield strength of at least 250 N/mm2 and/or an elongation at break of at least 5% have proven to be advantageous. The core, in particular the penetration core, may comprise or consist of hard material such as steel, sintered material, tungsten carbide, in particular containing tungsten or cobalt, in particular an alloy of 94% tungsten and 6% cobalt, tungsten carbide or hardened steel, in order to achieve the desired penetration performance of the projectile. Due to the high hardness of the core, it is virtually impossible to change its external shape after completion, so that manufacturing tolerances must be compensated for by the other parts of the projectile, in particular the guide shoe and the jacket. The front or outer end of the hard core sits more or less freely inside the ballistic jacket and only touches it in the portion of its circumferential shoulder. It also sits in the open part of the guide shoe. A modulus of elasticity of at least 500,000 N/mm2, in particular at least 550,000 N/mm2 or at least 600,000 N/mm2, a density value of at least 10,000 kg/m3, in particular at least 12,500 kg/m3 or 14,000 kg/m3 can be advantageous for the core. In other words, the jacket forms the outer shape of the projectile and accommodates the core consisting of a harder material and the guide shoe holding the core, which can, for example, be formed like a quiver and be open at the front in the direction of flight of the projectile in order to enable the core to be mounted in the shoe.
According to a further aspect of the disclosure, the guide shoe is provided in particular rear-sided with a barb-like structuring on its outer circumference, which is adapted to hook onto the jacket when the projectile is fired. The guide shoe can cut into the jacket or the jacket, in particular jacket material, can flow into the barb-like structuring. The structuring can have at least one cutting edge. This favors the fixation of jacket and guide shoe to each other and significantly improves the precision of the projectile, in particular because unwanted and uncontrolled relative movements are avoided. The barb-like structuring can be formed in such a way that the gas expansion force acting on the projectile when the projectile is fired in the firearm barrel and the pressing of the projectile through the firearm barrel, wherein a swirl transmission occurs, further amplifies the fixation between jacket and guide shoe, namely in that the barb-like structuring can be formed with sharp edges in particular so that it cuts into the material of the jacket.
In an exemplary further development of the jacket projectile according to the disclosure, the structuring is formed fully circumferentially, in particular in a thread-like manner. The thread-like structuring can be adapted to the direction of twist of the barrel of the firearm. The thread-like structuring can be a very fine structuring that is essentially formed close to the face. It has been found that even fine structuring is sufficient to achieve the desired effect of fixing the guide shoe and jacket together.
According to another exemplary further development, the structuring is formed by a sawtooth-like indentation and/or a sawtooth-like protrusion in relation to the outer circumference of the guide shoe. For example, the cutting edge has a sawtooth-like shape. The sawtooth-like indentation or the sawtooth-like protrusion can run all the way around the outer circumference of the projectile. Furthermore, if it is a thread-like structure, it is possible that the sawtooth-like indentation and/or the sawtooth-like protrusion winds around the outer circumference of the guide shoe with a plurality of circumferential windings. Furthermore, a plurality of indentations and/or protrusions may be present in the projectile rear, in particular evenly spaced apart and/or in particular formed in the same way. The sawtooth-like indentation and/or the sawtooth-like protrusion has a hooking flank oriented essentially perpendicular to the longitudinal axis of the projectile and a further flank arranged at an acute angle to it. The hooking flank is the flank that is mainly responsible for the hooking, in particular the cutting into the jacket.
According to a further exemplary further development of the jacket projectile according to the disclosure, the structuring, in particular the sawtooth-like indentation and/or the sawtooth-like protrusion, has a radial depth of less than 5%, in particular less than 4%, 3%, 2%, 1.5% or less than 1.25%, of an outer diameter of the guide shoe. In this respect, the structuring can be introduced very finely from the outside into the face of the guide shoe, such as ground in, turned in or the like.
According to a further aspect of the present disclosure, which can be combined with the preceding aspects and exemplary embodiments, a jacket projectile, in particular a partial jacket projectile or an armor-piercing projectile (AP projectile), is provided for ammunition with a caliber of, for example, less than 13 mm, in particular of less than 12.7 mm. AP projectiles form a special type of jacket projectile and are generally used in military portions to penetrate and destroy armored and/or hard faces of targets. They are also known as armor-piercing ammunition projectiles. Another special type of AP projectiles are armor-piercing incendiary projectiles (API projectiles) to which an additional flammable substance, for example zirconium, is added in order to produce an additional incendiary effect and/or arcing effect after penetrating the target, in particular its armor.
The jacket projectile according to the disclosure, also referred to as “projectile” for short, comprises a core, a jacket, in particular tapering ogive-like in the direction of flight and surrounding the core, and a guide shoe arranged between the core and the jacket. The core can be pressed with the guide shoe and joined as a unit with the jacket, in particular pressed therewith, in order to form the final projectile. The jacket comprises or consists of, for example, copper or alloys thereof, steel or other equivalent materials with regard to stability and press-through properties through the firearm barrel. Among other things, it is responsible for holding the hard core and the guide shoe of the core. In addition, the jacket assumes the internal and external ballistic functions of a normal projectile, as it can be easily formed into the required shape and external shape. The guide shoe comprises or consists, for example, of steel or aluminum or alloys thereof. A modulus of elasticity of 50,000 N/mm2 to 250,000 N/mm2, a density value in the range of 2,500 kg/m3 to 8,000 kg/m3, a yield strength of at least 250 N/mm2 and/or an elongation at break of at least 5% have proven to be advantageous. The core, in particular the penetration core, may comprise or consist of hard material such as steel, sintered material, tungsten carbide, in particular containing tungsten or cobalt, in particular an alloy of 94% tungsten and 6% cobalt, tungsten carbide or hardened steel, in order to achieve the desired penetration performance of the projectile. Due to the high hardness of the core, it is virtually impossible to change its external shape after completion, so that manufacturing tolerances must be compensated for by the other parts of the projectile, in particular the guide shoe and the jacket. The front or outer end of the hard core sits more or less freely inside the ballistic jacket and only touches it in the portion of its circumferential shoulder. It also sits in the open part of the guide shoe. A modulus of elasticity of at least 500,000 N/mm2, in particular at least 550,000 N/mm2 or at least 600,000 N/mm2, a density value of at least 10,000 kg/m3, in particular at least 12,500 kg/m3 or 14,000 kg/m3 can be advantageous for the core. In other words, the jacket forms the outer shape of the projectile and accommodates the core consisting of a harder material and the guide shoe holding the core, which can, for example, be formed like a quiver and be open to the front in the direction of flight of the projectile in order to enable the core to be mounted in the shoe.
According to a further aspect of the disclosure, an outer dimension of the guide shoe is oversized in relation to an inner dimension of the jacket and/or the jacket and the guide shoe are shape-matched to each other in such a way that an axial securing is formed, in particular a force-fitting and/or form-fitting axial securing. This prevents axial relative displacement between the jacket and the guide shoe. Due to the strong forces when the projectile is fired and/or when it is pressed through the barrel of the firearm, prior art projectiles tend to be accompanied by a relative movement between the guide shoe and jacket. This tendency can be prevented by the axial securing according to the disclosure, so that the precision of the projectile can be improved. The axial securing can alternatively or additionally be achieved or supported by a material-locking connection.
In a further exemplary embodiment of the present disclosure, the guide shoe has an oversize of 0.01 mm to 0.06 mm, in particular of 0.02 mm to 0.05 mm, in relation to the jacket and/or in the range of 2% to 7%, in particular of 2.5% to 6%, of the jacket wall thickness.
According to a further exemplary further development, the guide shoe and the jacket have a shape-matched protrusion/groove arrangement, according to which the guide shoe and the jacket interlock radially in one another for form-fitting axial securing against one another. It has been found that a minimum interlocking dimension in the single-digit percentage range in relation to the wall thickness of the jacket and/or the wall thickness of the guide shoe is already sufficient to realize axial securing. For example, the jacket has at least one groove on its inner circumference facing the guide shoe, in particular a plurality of grooves arranged at a particularly even distance in the longitudinal direction of the projectile, and/or the guide shoe has at least one protrusion on its outer circumference facing the jacket, in particular a plurality of protrusions arranged at a particularly even distance in the longitudinal direction of the projectile. The protrusions and grooves, in particular a pair of protrusion and recess assigned to each other, can be matched to each other in terms of their dimensions, at least their dimensions in the longitudinal direction of the projectile.
According to an exemplary further development of the jacket projectile according to the disclosure, the guide shoe has on its outer circumference, in particular on a cylindrical section of the guide shoe, at least one relief groove, in particular a plurality of relief grooves distributed at an in particular uniform distance in the longitudinal direction of the projectile. The at least one relief groove forms a groove of the protrusion/groove arrangement and/or is arranged adjacent to the protrusion of the protrusion/groove arrangement. The radial dimension of the relief grooves can therefore be significantly larger than the grooves of the protrusion/groove arrangement arranged in the inside of the casing.
In a further exemplary embodiment of the jacket projectile according to the disclosure, the jacket has an axial stop on its inner circumference for a front of the guide shoe oriented in the projectile flight direction. For example, the axial stop is realized by an indentation formed by means of a profile recess, with which the front of the guide shoe comes into stop contact. This amplifies the axial securing, as axial movement of the guide shoe beyond the axial stop is prevented. Furthermore, an inner face of the jacket directly adjacent to the axial stop, which can be formed cylindrically, for example, can be undersized in relation to the outer face of the guide shoe facing it, which can be directly adjacent to the front of the guide shoe, so that an interference fit is also realized in this respect, which, in combination with the form-fit via the axial stop, ensures improved axial securing.
According to a further exemplary embodiment, the guide shoe and the jacket or the guide shoe and the core are made from one piece. It has been found that the precision of the projectile can be increased by making the guide shoe and jacket or core and guide shoe in one piece. One of the reasons for this is that any relative movement between the guide shoe and jacket or guide shoe and core, which could have a negative effect on precision, can be eliminated.
In another exemplary further development, the jacket is formed in two parts. Alternatively, or additionally, the jacket can have a rear part and a front part connected to it. The rear part can be formed essentially cylindrically and surround or encapsulate the core rear-sided. The front part can be pressed or glued to the rear part or, for example, connected to it in a force-fitting and/or form-fitting manner. Furthermore, the front part can enclose or encapsulate the core front-sided, wherein in particular the front part and the core are dimensioned in relation to each other in such a way that a cavity remains at the front, which is unoccupied. The front part can front-sided be formed solid and/or consist of solid material.
According to a further aspect of the present disclosure, which can be combined with the preceding aspects and exemplary embodiments, a jacket projectile, in particular a partial jacket projectile or an armor-piercing projectile (AP projectile), is provided for ammunition with a caliber of, for example, less than 13 mm, in particular of less than 12.7 mm. AP projectiles form a special type of jacket projectile and are generally used in military portions to penetrate and destroy armored and/or hard faces of targets. They are also known as armor-piercing ammunition projectiles. Another special type of AP projectiles are armor-piercing incendiary projectiles (API projectiles) to which an additional flammable substance, for example zirconium, is added in order to produce an additional incendiary effect and/or arcing effect after penetrating the target, in particular its armor.
The jacket projectile according to the disclosure, also referred to as “projectile” for short, comprises a core, a jacket, in particular tapering ogive-like in the direction of flight and surrounding the core, and a guide shoe arranged between the core and the jacket. The core can be pressed with the guide shoe and joined as a unit with the jacket, in particular pressed therewith, in order to form the final projectile. The jacket comprises or consists of, for example, copper or alloys thereof, steel or other equivalent materials with regard to stability and press-through properties through the firearm barrel. Among other things, it is responsible for holding the hard core and the guide shoe of the core. In addition, the jacket assumes the internal and external ballistic functions of a normal projectile, as it can be easily formed into the required shape and external shape. The guide shoe comprises or consists, for example, of steel or aluminum or alloys thereof. A modulus of elasticity of 50,000 N/mm2 to 250,000 N/mm2, a density value in the range of 2,500 kg/m3 to 8,000 kg/m3, a yield strength of at least 250 N/mm2 and/or an elongation at break of at least 5% have proven to be advantageous. The core, in particular the penetration core, may comprise or consist of hard material such as steel, sintered material, tungsten carbide, in particular containing tungsten or cobalt, in particular an alloy of 94% tungsten and 6% cobalt, tungsten carbide or hardened steel, in order to achieve the desired penetration performance of the projectile. Due to the high hardness of the core, it is virtually impossible to change its external shape after completion, so that manufacturing tolerances must be compensated for by the other parts of the projectile, in particular the guide shoe and the jacket. The front or outer end of the hard core sits more or less freely inside the ballistic jacket and only touches it in the portion of its circumferential shoulder. It also sits in the open part of the guide shoe. A modulus of elasticity of at least 500,000 N/mm2, in particular at least 550,000 N/mm2 or at least 600,000 N/mm2, a density value of at least 10,000 kg/m3, in particular at least 12,500 kg/m3 or 14,000 kg/m3 can be advantageous for the core. In other words, the jacket forms the outer shape of the projectile and accommodates the core consisting of a harder material and the guide shoe holding the core, which can, for example, be formed like a quiver and be open to the front in the direction of flight of the projectile in order to enable the core to be mounted in the shoe.
According to a further exemplary embodiment of the present disclosure, the core has a rear-sided rear section which tapers, in particular conically, against the direction of flight, according to which an inner circumferential face of the guide shoe facing the rear section is shaped, which is arranged at a distance, in particular a constant distance, from the rear section. In order to obtain a jacket projectile that is as precise as possible, the inventors of the present disclosure have found that it is necessary for the core to be able to rest as entirely as possible in the projectile rear. This can be achieved by providing a small air gap transversely to the longitudinal axis direction of the jacket projectile as a result of the distance between the rear section of the core and the inner circumferential face of the guide shoe. This allows the core to be pushed, in particular pressed, completely into the rear of the projectile rear with repeatable accuracy. For example, the rear section and the inner circumferential face facing the rear section can extend essentially parallel, so that a gap or distance is created between them that is essentially constant over the entire longitudinal extension of the rear section. For example, the jacket has a hardness in the range of 45 HV to 120 HV, the guide shoe has a hardness in the range of 200 HV to 250 HV and/or the core has a higher hardness than the jacket, in particular a hardness of more than 920HV10 or 1200HV10.
In a further exemplary embodiment of the present disclosure, the distance is in the range of 0.025 mm-0.6 mm, in particular in the range of 0.05 mm-0.5 mm, in the range of 0.075 mm-0.4 mm or in the range of 0.1 mm-0.3 mm. These distance dimensions relate in particular to a jacket projectile with a caliber of less than 13 mm, in particular 9.5 mm.
According to a further exemplary embodiment of the jacket projectile according to the disclosure, the core and the guide shoe lie adjacent to each other in the rear section, in particular on both sides, i.e. flat on each other on both sides in relation to the longitudinal direction of the projectile or direction of flight. In particular, they are pressed against each other. For example, bottom faces of the core, guide shoe and, if applicable, jacket that lie on top of each other and are oriented transversely, in particular perpendicularly, to the longitudinal direction of the projectile are pressed against each other. It is clear that two pairs of pressing surfaces are each formed from two bottom faces facing each other, i.e. a core-guide shoe-pressing surface pair and a guide shoe-jacket-pressing surface pair. This double pressing of all three components against each other creates a particularly compact projectile rear, so that the precision of the projectile can be increased. The compact unit in the portion of the projectile rear also prevents relative movements, in particular around the longitudinal axis of the projectile, which have an uncontrolled and therefore negative effect on the ballistics and thus the precision of the projectile.
According to a further aspect of the present disclosure, which can be combined with the preceding aspects and exemplary embodiments, a jacket projectile, in particular a partial jacket projectile or an armor-piercing projectile (AP projectile), is provided for ammunition with a caliber of, for example, less than 13 mm, in particular of less than 12.7 mm. AP projectiles form a special type of jacket projectile and are generally used in military portions to penetrate and destroy armored and/or hard faces of targets. They are also known as armor-piercing ammunition projectiles. Another special type of AP projectiles are armor-piercing incendiary projectiles (API projectiles) to which an additional flammable substance, for example zirconium, is added in order to produce an additional incendiary effect and/or arcing effect after penetrating the target, in particular its armor.
The jacket projectile according to the disclosure, also referred to as “projectile” for short, comprises a core, a jacket, in particular tapering ogive-like in the direction of flight and surrounding the core, and a guide shoe arranged between the core and the jacket. The core can be pressed with the guide shoe and joined as a unit with the jacket, in particular pressed therewith, in order to form the final projectile. The jacket comprises or consists of, for example, copper or alloys thereof, steel or other equivalent materials with regard to stability and press-through properties through the firearm barrel. Among other things, it is responsible for holding the hard core and the guide shoe of the core. In addition, the jacket assumes the internal and external ballistic functions of a normal projectile, as it can be easily formed into the required shape and external shape. The guide shoe comprises or consists, for example, of steel or aluminum or alloys thereof. A modulus of elasticity of 50,000 N/mm2 to 250,000 N/mm2, a density value in the range of 2,500 kg/m3 to 8,000 kg/m3, a yield strength of at least 250 N/mm2 and/or an elongation at break of at least 5% have proven to be advantageous. The core, in particular the penetration core, may comprise or consist of hard material such as steel, sintered material, tungsten carbide, in particular containing tungsten or cobalt, in particular an alloy of 94% tungsten and 6% cobalt, tungsten carbide or hardened steel, in order to achieve the desired penetration performance of the projectile. Due to the high hardness of the core, it is virtually impossible to change its external shape after completion, so that manufacturing tolerances must be compensated for by the other parts of the projectile, in particular the guide shoe and the jacket. The front or outer end of the hard core sits more or less freely inside the ballistic jacket and only touches it in the portion of its circumferential shoulder. It also sits in the open part of the guide shoe. A modulus of elasticity of at least 500,000 N/mm2, in particular at least 550,000 N/mm2 or at least 600,000 N/mm2, a density value of at least 10,000 kg/m3, in particular at least 12,500 kg/m3 or 14,000 kg/m3 can be advantageous for the core. In other words, the jacket forms the outer shape of the projectile and accommodates the core consisting of a harder material and the guide shoe holding the core, which can, for example, be formed like a quiver and be open to the front in the direction of flight of the projectile in order to enable the core to be mounted in the shoe.
According to the further aspect of the present disclosure, a length of the core in the longitudinal direction of the projectile is in the range of 50%-95%, in particular in the range of 55%-90% or in the range of 60%-85%, of a total projectile length and/or a length/diameter ratio of the core is in the range of 3-7, in particular in the range of 4-6. When dimensioning the projectile and in particular the core, several boundary conditions must be considered, which are optimized as a result of the described dimensions or ratios. On the one hand, a core that is as long as possible allows better penetration of hard targets, such as steel targets in particular. On the other hand, more material is available for penetrating ceramic or other very hard targets. On the other hand, however, a core that is too long has the undesirable property of tending to break and thus significantly reducing the penetration performance of the projectile. In other words, a core that is as long as possible has a lot of energy for penetrating hard targets and sufficient material reserve for the abrasive penetration process of very hard materials such as ceramic or hardened steel, during which the core loses part of its mass, but has an upper limit in that breaking of the core is ruled out. In this context, it is also important to adjust the diameter of the core. It has been found that a core that is too thick or too thin leads to undesirable penetration results, such as breakage or a reduced cross-sectional load. It has been found that the described geometry ratios with regard to the length/diameter ratio meet these requirements.
According to a further aspect of the present disclosure, which can be combined with the preceding aspects and exemplary embodiments, a jacket projectile, in particular a partial jacket projectile or an armor-piercing projectile (AP projectile), is provided for ammunition with a caliber of, for example, less than 13 mm, in particular of less than 12.7 mm. AP projectiles form a special type of jacket projectile and are generally used in military portions to penetrate and destroy armored and/or hard faces of targets. They are also known as armor-piercing ammunition projectiles. Another special type of AP projectiles are armor-piercing incendiary projectiles (API projectiles) to which an additional flammable substance, for example zirconium, is added in order to produce an additional incendiary effect and/or arcing effect after penetrating the target, in particular its armor.
The jacket projectile according to the disclosure, also referred to as “projectile” for short, comprises a core, a jacket, in particular tapering ogive-like in the direction of flight and surrounding the core, and a guide shoe arranged between the core and the jacket. The core can be pressed with the guide shoe and joined as a unit with the jacket, in particular pressed therewith, in order to form the final projectile. The jacket comprises or consists of, for example, copper or alloys thereof, steel or other equivalent materials with regard to stability and press-through properties through the firearm barrel. Among other things, it is responsible for holding the hard core and the guide shoe of the core. In addition, the jacket assumes the internal and external ballistic functions of a normal projectile, as it can be easily formed into the required shape and external shape. The guide shoe comprises or consists, for example, of steel or aluminum or alloys thereof. A modulus of elasticity of 50,000 N/mm2 to 250,000 N/mm2, a density value in the range of 2,500 kg/m3 to 8,000 kg/m3, a yield strength of at least 250 N/mm2 and/or an elongation at break of at least 5% have proven to be advantageous. The core, in particular the penetration core, may comprise or consist of hard material such as steel, sintered material, tungsten carbide, in particular containing tungsten or cobalt, in particular an alloy of 94% tungsten and 6% cobalt, tungsten carbide or hardened steel, in order to achieve the desired penetration performance of the projectile. Due to the high hardness of the core, it is virtually impossible to change its external shape after completion, so that manufacturing tolerances must be compensated for by the other parts of the projectile, in particular the guide shoe and the jacket. The front or outer end of the hard core sits more or less freely inside the ballistic jacket and only touches it in the portion of its circumferential shoulder. It also sits in the open part of the guide shoe. A modulus of elasticity of at least 500,000 N/mm2, in particular at least 550,000 N/mm2 or at least 600,000 N/mm2, a density value of at least 10,000 kg/m3, in particular at least 12,500 kg/m3 or 14,000 kg/m3 can be advantageous for the core. In other words, the jacket forms the outer shape of the projectile and accommodates the core consisting of a harder material and the guide shoe holding the core, which can, for example, be formed like a quiver and be open to the front in the direction of flight of the projectile in order to enable the core to be mounted in the shoe.
According to a further aspect of the present disclosure, the guide shoe is provided on its inner circumferential face facing the core with an annular recess, in the portion of which the core and the guide shoe are contactless. As a result, a cavity is formed between the guide shoe and the projectile core, which is in particular fully circumferentially formed. This internal cavity is used in particular for taring. This allows the center of gravity of the jacket projectile to be adjusted within a certain range, thereby increasing the precision of the projectile. In addition, the internal cavity or undercut also has the positive effect that, on the one hand, a further damping property is realized between the guide shoe and projectile core, as the external guide shoe can move radially inwards into the cavity, which in turn can positively reduce the load on the barrel of the firearm and, on the other hand, a further damping possibility is realized compared to pressing into the rifling-field profile. The elastic bridge formed in this way counteracts the extremely abrupt pressing in or pressing through of the projectile through the firearm barrel or into the rifling-field profile of the firearm barrel during the firing process. The annular recess can be open in the longitudinal direction of the projectile. Further, a maximum length of the annular recess in the longitudinal direction of the projectile can be designed in such a way that the core is pressed in over a length of at least the core diameter.
According to an exemplary further development, the annular recess has a radial depth transverse to the longitudinal direction of the projectile of at most 50% of the wall thickness of the guide shoe adjacent to the annular recess. In order to limit the elastic bridge or the deformation property and at the same time maintain the stability of the guide shoe so that it can reliably perform its guiding function, a maximum radial depth of the ring recess must be maintained.
In a further exemplary embodiment of the jacket projectile according to the disclosure, the annular recess is arranged on a front-sided end section of the guide shoe facing the taper, in particular is arranged in such a way that a dimension in the longitudinal direction of the projectile of a front end of the guide shoe delimiting the annular recess in the longitudinal direction of the projectile, such as a radial flange, is in the range of 90% to 110%, in particular in the range from 95% to 105%, of the wall thickness of the guide shoe.
In a further exemplary embodiment of the jacket projectile according to the disclosure, a rear-sided end of the annular recess facing away from the taper lies at most at the axial height of the center of gravity of the jacket projectile. This ensures good taring of the jacket projectile by allowing the center of gravity of the projectile to be deliberately adjusted so that its precision, terminal velocity and ballistics are optimized.
In a further exemplary embodiment of the present disclosure, the core is dimensioned in such a way that front-sided a cavity exists or remains, wherein in particular an insert is arranged in the cavity. The core can be arranged in the cavity of the projectile jacket and/or dimensioned in such a way that a front-sided cavity is unoccupied by the core. In other words, the core does not completely fill the cavity, in particular front-sided, in particular immediately adjacent to the projectile tip up to a certain axial position in front of the projectile tip. The core can completely fill the cavity, with the exception of the front-sided unoccupied cavity. For example, the projectile jacket in the rear section is shaped in such a way that it surrounds the core rear-sided. The rear-sided surrounding can be understood to mean that the jacket is also closed rear-sided. However, it is also conceivable that the jacket remains open rear-sided or leaves an opening in which portion of the core is accessible rear-sided.
According to an exemplary further development of the jacket projectile according to the disclosure, the insert is dimensioned and/or made of a material such that the center of gravity of the jacket projectile is shifted to the rear compared to a jacket projectile without cavity, i.e. a jacket projectile in which the core completely fills the hollow projectile jacket and is fully in contact with the projectile jacket. The core may have a lower density, in particular a lower specific density, than the projectile core and/or the projectile jacket. The inventors of the present disclosure have thus surprisingly found a way to transfer the advantages of hollow tip projectiles to jacket projectiles. A significant advantage of the present disclosure is that the center of gravity of the jacket projectile is shifted to the back, towards the projectile rear. This results in significant advantages in terms of the ballistics and/or precision of the jacket projectile.
According to an exemplary further embodiment of the jacket projectile according to the disclosure, the insert is made of a material which has a lower density, in particular a lower specific density, than the material of the projectile jacket and/or the projectile core. In particular, the insert is made of aluminum, magnesium, brass, steel or plastic. It is clear that the respective material must be selected in such a way that the desired rearward shift of the center of gravity is achieved to increase the precision and/or ballistics of the jacket projectile.
In the following description of exemplary embodiments of jacket projectiles according to the disclosure, a jacket projectile according to the disclosure is generally provided with the reference number 1. The same or similar reference signs are used for the same or similar components. The exemplary embodiments according to the enclosed figures show an embodiment of a jacket projectile according to the disclosure as a partial jacket projectile, wherein it should be clear that this is only to be understood as an example and that the corresponding embodiments and designs are also transferable to a full jacket projectile.
The jacket projectile 1 according to the disclosure may include the following main components: A jacket 3 determining the outer and inner ballistic shape and in particular tapering ogive-like, in particular with a hardness in the range of 45 HV to 120 HV; a hard core 5 arranged in the jacket 3, in particular with a higher hardness than the jacket material and/or with a length LK in the longitudinal direction of the projectile and a diameter D1; and a guide shoe 7 arranged likewise within the jacket 3 and receiving and fixing the core 5 and having a length LF in the longitudinal direction of the projectile. The jacket 3 is the component that comes into contact with the firearm barrel and is also responsible for the interaction between projectile 1 and the firearm barrel. The core 5 is made of a harder material than the jacket 3, for example hard metal, in particular containing tungsten, in particular tungsten carbide, cobalt, or steel, in particular hardened steel, in order to achieve the desired penetration performance of the projectile. The guide shoe 7, into which the projectile core 5 can be pressed so that core 5 and guide shoe 7 can be inserted into the jacket as an assembly unit, essentially fulfills two functions. Firstly, it is designed to fix or hold the core 5 in place in order to prevent relative movements between the core 5 and jacket 3, which have a negative effect on the precision of the projectile 1. On the other hand, the guide shoe 7 also contributes to increasing the penetration energy or penetration force of the projectile 1. The guide shoe can, for example, be made of steel or aluminum or comprise these materials.
In
The jacket 3 also has an essentially cylindrical part adjoining the ogive-shaped projectile front 11, forming a guide band 12, which essentially forms the maximum outer diameter of the projectile and is designed primarily to engage with the barrel of the firearm. The projectile rear 9, which according to the exemplary embodiment is slightly inclined with respect to the projectile center axis M and finally merges into a planar projectile bottom 15, adjoins the guide band 12 at the rear.
The jacket projectile 1 according to the disclosure is arranged in such a way that an optimum geometric ratio is present in order to achieve the desired results in terms of barrel load, precision and penetration. The core 5 has a length in the longitudinal direction of the projectile in the range of 50% to 95% of a total projectile length. Furthermore, a length/diameter ratio of the core 5 is in the range of 3 to 7.
With reference to
The guide shoe 7 has an annular recess 29 on its inner circumferential face 27 facing the core 5, which can completely encircle the core 5 and has a substantially rectangular cross-section. In the portion of the annular recess 29, the guide shoe 7 and the jacket 5 are free of contact with each other. The ring recess 29 is designed in particular for taring. This allows the center of gravity of the jacket projectile 1 to be adjusted in a certain portion, thereby improving the precision of the projectile 1. The annular recess 29 also has the positive side effect that, on the one hand, a further damping device is realized in the event of any material deformations, in particular with regard to the external pressing into the rifling-and-field profiling of the firearm barrel, which can result in deformation of the jacket 3 and/or the guide shoe 7 from radially outwards to radially inwards. The elastic bridge thus formed between the firearm barrel and the core 5 thus counteracts the extremely abrupt pressing of the projectile 1 through the firearm barrel and in particular the pressing of the projectile 1 into the rifling-and-field profiling during the firing process.
As can be seen in particular in
With reference to
It can also be seen in
Referring again to the protrusions 33 formed on the outer circumference of the guide shoe substantially over its entire cylindrical extension, each forming a relief groove 59 between them, which allow the material of the jacket 3 to ensure a deflection into these relief grooves 59 in the event of radial pressures occurring, for example when the projectile is fired and/or when it is pressed through the barrel of the firearm, in order to avoid overloading the jacket material. According to the disclosure, it was found that the gas slip in the firearm barrel has a significant influence on the final precision of the projectile 1, because due to the gas slip, the jacket 3 is pressed so firmly against the guide shoe 7 that the protrusions 33 of the guide shoe 7 connect with the jacket 3. In order to prevent the protrusions from becoming noticeable as far as the outside of the jacket 3, the protrusions 33 according to the exemplary embodiment of the jacket projectile 1 according to the disclosure shown in
With reference to
Furthermore, as can be seen in
A further difference compared to the previous embodiments is that the jacket 3, in particular the front part 97, is closed front-sided and completely covers the core 5 from the surroundings. Furthermore, the front part 87 is solid and/or formed from solid material, in particular in order to amplify the penetration performance of the projectile 1.
The features disclosed in the above description, the figures and the claims can be of importance both individually and in any combination for the realization of the disclosure in the various embodiments.
To enable those skilled in the art to better understand the solution of the present disclosure, the technical solution in the embodiments of the present disclosure is described clearly and completely below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the embodiments described are only some, not all, of the embodiments of the present disclosure. All other embodiments obtained by those skilled in the art on the basis of the embodiments in the present disclosure without any creative effort should fall within the scope of protection of the present disclosure.
It should be noted that the terms “first”, “second”, etc. in the description, claims and abovementioned drawings of the present disclosure are used to distinguish between similar objects, but not necessarily used to describe a specific order or sequence. It should be understood that data used in this way can be interchanged as appropriate so that the embodiments of the present disclosure described here can be implemented in an order other than those shown or described here. In addition, the terms “comprise” and “have” and any variants thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or equipment comprising a series of steps or modules or units is not necessarily limited to those steps or modules or units which are clearly listed, but may comprise other steps or modules or units which are not clearly listed or are intrinsic to such processes, methods, products or equipment.
References in the specification to “one embodiment,” “an embodiment,” “an exemplary embodiment,” etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.
The exemplary embodiments described herein are provided for illustrative purposes, and are not limiting. Other exemplary embodiments are possible, and modifications may be made to the exemplary embodiments. Therefore, the specification is not meant to limit the disclosure. Rather, the scope of the disclosure is defined only in accordance with the following claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102023105715.4 | Mar 2023 | DE | national |
