JACKET PROJECTILE

Abstract

A jacket projectile, in particular an armor-piercing projectile, for ammunition, in particular with a caliber of less than 13 mm, may include a core, a jacket, in particular tapering ogive-like and surrounding the core, and a guide shoe arranged between the core and the jacket. The material of the jacket and the guide shoe may be matched to one another in such a way that a quotient of a modulus of elasticity/density ratio

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This patent application claims priority to German Patent Application No. 10 2023 105716.2, filed Mar. 8, 2023, which is incorporated herein by reference in its entirety.

BACKGROUND

Field

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, for example, less than 13 mm, in particular less than 12.7 mm. Furthermore, the present disclosure relates to ammunition with such a jacket projectile.

Related Art

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.

With AP projectiles in the small caliber range, there is often the problem of the limited size of the penetration core. It is obvious that the volume-to-surface ratio is significantly worse compared to medium and large caliber ammunition.

BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES

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.

FIG. 1 an exemplary embodiment of a jacket projectile according to the disclosure in sectional view;

FIG. 2 a detailed view II from FIG. 1;

FIG. 3 a detailed view III from FIG. 1;

FIG. 4 a detailed view IV from FIG. 1;

FIG. 5 an enlarged view of an exemplary embodiment of a guide shoe of a jacket projectile according to the disclosure;

FIG. 6 a detailed view VI from FIG. 5;

FIG. 7 a detailed view VII from FIG. 6;

FIG. 8 an exemplary embodiment of a rear, a core, of an exemplary embodiment of a jacket projectile according to the disclosure;

FIG. 9 a further exemplary embodiment of the rear of the core;

FIG. 10 a further exemplary embodiment of a jacket projectile according to the disclosure in sectional view; and

FIG. 11 a sectional view of a further exemplary embodiment of a jacket projectile according to the disclosure.

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.

DETAILED DESCRIPTION

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 create a projectile with improved penetration performance.

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 light signal 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 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 material of the jacket and the guide shoe are matched such that a quotient of an E-modulus/density ratio

$\left(\frac{E_{\mathrm{guide}\mathrm{shoe}}}{{\rho }_{\mathrm{guide}\mathrm{shoe}}}\right)$

of the guide shoe to an E-modulus/density ratio

$\left(\frac{E_{\mathrm{core}}}{{\rho }_{\mathrm{core}}}\right)$

of the core is greater than 0.5, in particular greater than 0.55 or greater than 0.6. In particular, the ratio is at most 1. The inventors of the present disclosure have discovered that it is advantageous with regard to the penetration capability and the vibration damping of the core during the penetration process if the E-modulus/density ratio of the guide shoe and core are in a similar range. This improves the vibration damping of the core within the guide shoe in particular. 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 an exemplary embodiment of the jacket projectile according to the disclosure, the core is made of hard metal and/or has a unitless E-modulus/density ratio in the range of 40 to 45. Alternatively, or additionally, the guide shoe is made of steel or aluminum and/or has a unitless E-modulus/density ratio in the range of 25 to 30. For example, in the case where the core is made of tungsten carbide, this results in a modulus of elasticity/density ratio of 42. Depending on whether steel or aluminum is used for the guide shoe, wherein a modulus of elasticity/density ratio of 27 or 26 is obtained, the ratio is approximately 0.62. Such values have proven to be particularly good with regard to the vibration damping of the core.

In a further exemplary embodiment of the present disclosure, the E-modulus/density ratio of the guide shoe and the E-modulus/density ratio of the core are matched to each other in such a way that vibrations of the core are damped by the guide shoe. It has been found that particularly good damping properties are achieved if the ratios are in a similar range and/or the materials are selected in such a way that particularly good vibration damping is achieved. Various material constellations, such as carbide for the core and steel or aluminum for the guide shoe, have proven to be particularly advantageous for this purpose.

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 light signal 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 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 the further aspect of the present disclosure, a minimum wall thickness D₂ of the guide shoe in the portion of a cylindrical hull section is in the range of 10% to 20% of a maximum core diameter D₁, in particular the minimum wall thickness D₂ is about 15% of the maximum core diameter D₁. It has been found that a certain wall thickness of the guide shoe is necessary in order to be able to absorb or reduce the external loads associated with the impact, in particular deformation forces, and to be able to withstand them. The core can break, especially when penetrating extra-hard targets such as ceramics. The task of the guide shoe is then to enclose the core as good as possible and protect it from separation from the rest of the projectile. Furthermore, a crack in the core does not have such drastic consequences if it is still enclosed in or guided by the guide shoe. The cylindrical hull section has been identified as one of the neuralgic points for the strength of the guide shoe with regard to the protection of the core.

In an exemplary embodiment of the jacket projectile according to the disclosure, the guide shoe has a rear-sided bottom section, tapering in particular conically against the direction of flight, the minimum wall thickness D₃ of which is at least 90% of the wall thickness D₂ of the guide shoe. The inventors of the present disclosure have identified the rear-sided bottom section, which tapers further in the direction of the projectile rear or projectile bottom, as a further critical point with regard to the strength of the guide shoe, as there is a change in the contour of the guide shoe and the core, which thus represents a weak point in terms of strength. It was therefore found that this section must not fall below a certain lower wall thickness limit.

According to a further exemplary further development of the jacket projectile according to the disclosure, the guide shoe has a rear-sided bottom forming one end of the guide shoe, the wall thickness D₄ of which is at least 100%, in particular at least 110%, 120% or at least 130%, and/or at most 200% of the core diameter D₁. The bottom of the guide shoe, which points against the direction of flight and is directed directly in the direction of the forces generating the gas pressure responsible for the launch, must also be particularly stable according to the disclosure in order to ensure the function of enclosing or retaining the core.

In a further exemplary embodiment of the jacket projectile according to the disclosure, a length of the guide shoe L_F in the longitudinal direction of the projectile is at least 100%, in particular at least 200% and/or is in the range of 300% to 400% of the caliber diameter. Alternatively, or additionally, a length of the guide shoe L_F in the longitudinal direction of the projectile corresponds to at least one length of the core L_K in the longitudinal direction of the projectile.

According to a further exemplary embodiment, bottom faces of the core, jacket and guide shoe 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 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 therefore negative effect on the ballistics and thus the precision of the projectile.

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.

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, 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.

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 essentially comprises 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 L_K 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 L_F 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 FIG. 1, the jacket projectile 1 according to the disclosure is shown in sectional view and oriented in a flight direction F in such a way that a projectile rear 9 is arranged at the rear with respect to the flight direction F, and a projectile front 11 is arranged at the front with respect to the flight direction F. As can be seen in FIG. 1, the jacket 3 tapers in the direction of flight F ogive-like and is essentially hollow in the portion of the projectile front 11. Further components can be present in the cavity 13 formed in this way, depending on the desired function of the jacket projectile 1. For example, an insert in the form of a weight balancing element can be present in the cavity 13 in order to be able to adjust the center of gravity of the jacket projectile 1, which can also only partially fill or occupy the cavity 13, for example. With regard to the provision of front-sided inserts in a front-sided cavity area, reference is made to the German patent application DE 10 2020 133 371, the relevant content of which is incorporated herein by reference.

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 FIGS. 2 to 9, aspects according to the disclosure and exemplary embodiments of jacket projectiles 1 according to the disclosure are explained in more detail.

FIG. 2 shows a detailed section II from FIG. 1, which shows a front-sided axial securing 17 between guide shoe 7 and jacket 3 and ensures a force-fitting and/or form-fitting fixing of jacket 3 and guide shoe 7 to each other, so that axial relative movements between jacket 3 and guide shoe 7 can be delimited or prevented, in particular when the projectile 1 is fired and/or when it is pressed through the barrel of the firearm. According to the embodiment shown in FIG. 2, the axial securing 17 is formed by the interaction of an axial stop 19 provided on an inner circumference of the jacket 3, with which a front face 21 of the guide shoe 7 oriented in the projectile flight direction F can come into stop contact. To form the axial stop 19, a substantially cylindrical indentation 25 can be formed on the inner circumference 23 of the jacket 3, according to which the front section of the guide shoe 7 can be shaped.

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 FIG. 2 and enlarged in FIG. 3, an internal dimension of the jacket 3 is slightly undersized in relation to an external dimension of the guide shoe 7, so that compression occurs, which in turn results in a force-fitting and/or form-fitting fixing of jacket 3 and guide shoe 7 together. To amplify the axial securing of the guide shoe 7 and jacket 3 together, the jacket 3 and the guide shoe 7 have a shape-matched protrusion/groove arrangement 31, according to which the guide shoe 7 and jacket 3 interlock radially with each other for form-fitting, axial securing together. FIG. 3 in particular shows that a plurality of radial protrusions 33 are provided on the outer circumference 35 of the guide shoe 7, which are arranged at a particularly even distance from one another in the longitudinal direction of the projectile and protrude or interlock radially into the material of the jacket 3. Corresponding grooves 37 are formed on the inner circumference 23 of the jacket, which can either be manufactured in advance or are produced as a result of the guide shoe 7 and jacket 3 being pressed against each other.

With reference to FIG. 4, which shows a detailed view IV from FIG. 1, further exemplary embodiments of jacket projectiles 1 according to the disclosure are explained. The bottom faces 39 to 45 of core 5, guide shoe 7 and jacket 3, which lie on top of each other and are oriented perpendicular to the longitudinal direction of the projectile, are pressed against each other so that two pairs of pressed faces 39, 41 and 43, 45 are formed. By pressing all three components in the rear area of jacket 3, guide shoe 7 and core 5 against each other, a very compact unit is formed in the rear, which in turn has a positive effect on the precision of projectile 1. This is because the compactness in the rear area, where the massive gas expansion forces are exerted by the firearm when the projectile is fired, means that any changes in geometry or relative movements of the individual components to each other can be reliably counteracted.

It can also be seen in FIG. 4 that the core 5 has a rear-sided rear section 47 that tapers conically against the direction of flight F, according to which an inner circumferential face 49 of the guide shoe 7 facing the rear section 47 is shaped. The circumferential face 49 and the rear section 47 are arranged at an essentially constant distance s from each other, which can lie in particular in the range of 0.1 mm to 0.3 mm and favors the mating of the three components of core 5, guide shoe 7 and jacket 3, as there is a certain amount of movement in the radial direction around the dimension s. The air gap s favors reproducibility when inserting the core 5 into the guide shoe 7.

FIG. 5 shows an exemplary embodiment of a guide shoe 7 of a jacket projectile 1 according to the disclosure in isolated representation. From the combined view of FIGS. 5 and 6, which shows a detailed view according to VI from FIG. 5, it can be seen that the guide shoe is provided rear-sided with a barb-like structuring 51 on its outer circumference, which is adapted to hook onto the jacket 3 when the projectile 1 is fired. The hooks can be realized, for example, by the barb-like structuring 51 cutting into the jacket 3. This further amplifies the axial fixing of jacket 3 and guide shoe 7 to each other in order to prevent any external forces that could result in a relative displacement of guide shoe 7 and jacket 3. The structuring 51 can be fully formed in the manner of a thread and, in particular, extend around the outer circumference of the guide shoe 7 like a thread. In the example of FIGS. 5 to 7, the barb-like structuring 51 is formed by a plurality of sawtooth-like indentations 53 arranged at a particularly uniform distance from one another in the longitudinal direction of the projectile, which have a hooking flank 55 oriented perpendicular to the projectile longitudinal axis and a further flank 57 arranged at an acute angle thereto. In the example shown in FIGS. 5 to 7, a cross-section of the sawtooth-like indentations is essentially triangular in shape.

FIG. 5 also shows another exemplary design feature of the guide shoe 7. On bottom faces 39 of the guide shoe 7 oriented in the opposite direction to the direction of flight F, a recess 83 is introduced. The recess 83 may include a tapering or be formed with an undercut, as shown in FIG. 5, with an essentially triangular cross-section, which is adapted to compensate for the massive stresses occurring as a result of the firing of the projectile 1. The geometric ratios of the guide shoe 7 are particularly important for the penetration process and a high penetration rate. A minimum wall thickness D₂ of the guide shoe 7 in the region of a cylindrical hull section 79 is in the range of 10% to 20% of a maximum core diameter D₁. The guide shoe 7 also has a rear bottom section 77 that tapers, in particular conically, against the direction of flight and whose minimum wall thickness D₃ is at least 90% of the wall thickness D₂. In addition, the guide shoe 7 comprises a rear-sided bottom 81 forming one end of the guide shoe 7, the wall thickness D₄ of which is at least 100%, in particular at least 110%, 120% or at least 130%, and/or at most 200% of the core diameter D₁.

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 FIG. 5 have a decreasing thickness in the projectile rear in the projectile flight direction, because it has been found that the gas slip decreases in the projectile flight direction between the barrel of the firearm and the projectile 1. In other words, the gas slip is greatest in the portion of the projectile rear 9 and decreases towards the projectile front 11. The varying thickness of the protrusions 33 is matched to the extent of the gas slip when the projectile 1 is fired. The protrusion/relief groove gradation formed in this way achieves a reduction in the press-in resistance in the barrel of the firearm. As a result, the service life of the firearm barrel can be increased and high projectile velocities can be achieved.

With reference to FIGS. 8 and 9, exemplary embodiments of cores 5 of jacket projectiles 1 according to the disclosure are shown schematically. The focus of the embodiments of the cores 5 is in its rear region 61. In the embodiments of the core 5 according to FIGS. 8 and 9, it is common that the core 5 is provided rear-sided with a profiling 63 on its outer circumference, according to which the guide shoe 7 is adapted in a shape-complementary manner in such a way that an anti-twist securing is formed between the guide shoe 7 and the core 5. The anti-twist securing prevents any relative movements between core 5 and guide shoe 7 that could have a negative effect on precision. The profiling 63 is formed completely circumferentially and has a wave-like contour, which in turn is formed in the opposite direction on the inner circumference of the guide shoe 7, so that the anti-twist securing is reliably formed. According to FIG. 8, the profiling section 65 delimited by the profiling 63 has six flattenings distributed in the circumferential direction and, in particular, identically formed, and the embodiment according to FIG. 9 has eight flattenings 67, 69, which have a different radial curvature with respect to the projectile center axis M compared to a core section 71 adjacent to the profiling section 65. In the embodiment according to FIG. 8, the profiling section is also inclined at an angle in the range of 10° to 30° relative to the center axis M. Furthermore, the flattenings 67 open directly into one another. In an embodiment according to FIG. 9, the profiling section 65 is essentially cylindrical and the flattenings 69 distributed in the circumferential direction are each separated from one another by a cylindrical segment section 73. Furthermore, the profiling section 65 is displaced radially inwards with respect to the adjoining core section 71, which is achieved by a profiling step 75 inclined at an angle α with respect to the center axis M.

FIG. 10 shows an embodiment of a projectile 1 according to the disclosure in which the annular recess 29 is formed open in the longitudinal direction of the projectile. Furthermore, a length L in the longitudinal direction of the projectile according to the embodiment in FIG. 10 is greater than in FIG. 1, with the maximum length L being designed such that the core 5 is pressed in over a length of at least the core diameter.

FIG. 11 shows another exemplary embodiment of a jacket projectile 1 according to the disclosure. Identical or similar components are provided with identical or similar reference signs. Furthermore, essentially only the differences arising in relation to the previous embodiments are discussed. The main difference between the embodiment according to FIG. 11 and the previous embodiments is that the jacket 3 and the guide shoe 7 are made from one piece, indicated by the reference sign 85. In this respect, any relative movements occurring between the guide shoe 7 and jacket 3, which would impair precision, can be ruled out. It can be seen that the wall thickness of the one-piece guide shoe-jacket component 85 formed in this way is thickened in comparison to the respective guide shoe 7 or the jacket 3 of the previous embodiments and essentially corresponds to the summed-up wall thickness of jacket 3 and guide shoe 7, in particular in order to realize essentially similar properties in the end ballistics. The guide shoe-jacket component 85 has arear-sided, inner-sided taper and is adapted to the core rear section 47 and its rear profiling 91.

Furthermore, as can be seen in FIG. 11, the core 5 is completely enclosed or encapsulated. According to the embodiment shown in FIG. 11, this is realized by a two-part jacket comprising a rear part 89 and a front part 87, which are connected to one another in the portion of overlapping contact flanges 93, 95. The connection can be force-fitting and/or form-fitting or also material-fitting.

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.

FIG. 11 also shows that the annular recess 29 is delimited at the front by one of the contact flanges 93, 95, wherein, according to the exemplary embodiment in FIG. 11, the inner-sided contact flange 95 of the front part 87 forms the boundary.

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.

LIST OF REFERENCE SYMBOLS

• • 1 Jacket projectile
  • 3 Jacket
  • 5 Core
  • 7 Guide shoe
  • 9 Projectile rear
  • 11 Projectile front
  • 12 Guide band
  • 13 Cavity
  • 15 Bottom
  • 17 Axial securing
  • 19 Axial stop
  • 21 Front face
  • 23 Inner circumference
  • 25 Indentation
  • 27 Inner circumference
  • 29 Annular recess
  • 31 Protrusion/groove arrangement
  • 33 Protrusion
  • 35 Groove
  • 37 Groove
  • 39,41,43,45 Bottom face
  • 47 Rear section
  • 49 Inner circumferential face
  • 51 Structuring
  • 53 Indentation
  • 55 Hooked flank
  • 57 Flank
  • 59 Relief groove
  • 61 Core rear
  • 63 Profiling
  • 65 Rear section
  • 67,69 Flattening
  • 71 Core section
  • 73 Cylinder segment section
  • 75 Profiling step
  • 77 Bottom section
  • 79 Hull section
  • 81 Bottom
  • 83 Recess
  • M Center axis
  • F Projectile flight direction
  • S Distance
  • D₁ Core diameter
  • D₂ Wall thickness of the hull section of the guide shoe
  • D₃ Wall thickness of the bottom section of the guide shoe
  • D₄ Wall thickness of the bottom of the guide shoe
  • L_F Length of the guide shoe
  • L_K Length of the core

Claims

1. A jacket projectile for ammunition, the jacket projectile comprising: a core;a jacket surrounding the core; anda guide shoe arranged between the core and the jacket,wherein a material of the jacket and the guide shoe are matched to one another to provide a quotient of a modulus of elasticity/density ratio

2. The jacket projectile according to claim 1, wherein: the core is made of metal, and/or has a unitless modulus of elasticity/density ratio of 40 to 45; and/orthe guide shoe is made of steel or aluminum, and/or has a unitless modulus of elasticity/density ratio of 25 to 30.

3. The jacket projectile according to claim 1, wherein the guide show is adapted to dampen vibrations of the core based on a matching of the modulus of elasticity/density ratio

4. A jacket projectile for ammunition, comprising: a core;a jacket and surrounding the core; anda guide shoe arranged between the core and the jacket, wherein: a length of the core in a longitudinal direction of the projectile of 50% to 95% of a total projectile length; and/ora length/diameter ratio of the core is 3 to 7.

5. A jacket projectile for ammunition, comprising: a core;a jacket and surrounding the core; anda guide shoe arranged between the core and the jacket;wherein a first minimum wall thickness of the guide shoe in a portion of a cylindrical hull section is 10% to 20% of a maximum core diameter.

6. The jacket projectile according to claim 5, wherein the guide shoe has a rear-sided bottom, wherein a first section of the rear-sided bottom tapers against a direction of flight, a second minimum wall thickness of the first section of the rear-sided bottom being at least 90% of the first minimum wall thickness of the guide shoe.

7. The jacket projectile according to claim 5, wherein a second section of the guide shoe forming one end of the guide shoe has a third wall thickness of at least 100% of the core diameter.

8. The jacket projectile according to claim 5, wherein a length of the guide shoe in a longitudinal direction of the projectile; is at least 100% of a caliber diameter of the jacket projectile, and/or corresponds to at least one length of the core in the longitudinal direction of the projectile.

9. The jacket projectile according to claim 5, wherein bottom faces of the core, jacket, and guide shoe are adapted to lie on top of one another, be oriented transversely to a longitudinal direction of the projectile, and be pressed against one another.

10. The jacket projectile according to claim 5, wherein the core comprises a rear-sided rear section which tapers against a direction of flight and which is arranged at a constant distance from a tail section.

11. The jacket projectile according to claim 10, wherein the constant distance is 0.025 mm to 0.6 mm.

12. The jacket projectile according to claim 5, wherein: the guide shoe and the jacket are made from one piece; or the core and the guide shoe are made from one piece.

13. The jacket projectile according to claim 5, wherein the jacket is formed in two parts and/or has a hull-like.

14. The jacket projectile according to claim 5, wherein the jacket comprises a cylindrical, rear part and a front part connected thereto, the core being encapsulated by the front part and the rear part.

15. The jacket projectile according to claim 2, wherein the guide show is adapted to dampen vibrations of the core based on a matching of the modulus of elasticity/density ratio

16. The jacket projectile according to claim 1, wherein: a length of the core in a longitudinal direction of the projectile of 50% to 95% of a total projectile length; and/ora length/diameter ratio of the core is 3 to 7.

17. The jacket projectile according to claim 1, wherein a minimum wall thickness of the guide shoe in a portion of a cylindrical hull section is 10% to 20% of a maximum core diameter.