Method and tool for making a base piece of a multi-part cartridge case, base piece, and cartridge case

Abstract

The present invention relates to a method for producing a base piece for receiving a primer for a multi-part cartridge case, in which a withdrawal groove for engagement by a firearm ejector is produced by deformation before a receptacle for a case jacket of said multi-part cartridge case for receiving a projectile is produced, in particular by deformation, and also to a tool arrangement for producing the base piece, the base piece and the cartridge case.

Description

[Technical field]

[0001] The present invention relates to a method and tool arrangement for making a base piece of a multi-component cartridge case. Furthermore, the present invention relates to a base piece for a multi-component cartridge case, and to a multi-component cartridge case. [Background technology]

[0002] Multi-part cartridge cases are basically known and are divided at least into a base piece facing the primer and receiving it, and a case jacket rigidly connected to the base piece for receiving the projectile. The base piece usually has an extraction groove that supports the removal of the fired and empty cartridge case. Via the extraction groove, a so-called extractor of the firearm conveys the empty cartridge case to a so-called ejector of the firearm, which finally pushes out the empty cartridge. The extraction groove is molded in the peripheral wall of the annular base piece as a circumferential groove or recess. The circumferential groove or recess has a rear step edge oriented essentially transversely to the longitudinal axis, a radially inner base surface oriented essentially in the longitudinal axis, and a transition edge adjacent to the base surface and inclined to the longitudinal axis. In the prior art, extraction grooves have been produced so far by machining, which has proven to be less than optimal in terms of production costs and advantageous mass production. In the field of production of one-piece cartridge cases, there is already a prior art approach to produce extraction grooves by deformation. Here, so-called segmented punch and die tool configurations are used, whereby the inner geometric shape for holding the projectile and primer is first produced and finished, and the drawing grooves are then introduced on the outside in a subsequent process step. These punch and die tool configurations cannot be easily transferred to multi-component cartridge cases.

[0003] For example, FR1113479 discloses a three-part cartridge case consisting of a base piece with a drawing groove, a case jacket and fastening parts. Another multi-part cartridge case in which the base piece is also provided with a drawing groove is known from US2019 / 0226817.

[0004] The inventors of the present invention have found many potential improvements with regard to the drawing groove, i.e., on the one hand, with regard to manufacturing tolerances and, on the other hand, with regard to the achievable retention force for fastening the base piece and the case jacket. It has turned out that it is not always possible to ensure that the retention force between the base piece and the case jacket of a multi-part cartridge case can reliably withstand the high forces when a firearm is fired. Neither the production of the drawing groove by machining nor the conventional solutions for the production by cold forming can reliably guarantee the desired manufacturing tolerances. In particular, the production of the drawing groove using a segmented tool has turned out to be particularly disadvantageous, since the segmented tool can cause surface defects on parts of the drawing groove that are detrimental to the drawing function. Summary of the Invention

[0005] One object of the present invention is to overcome the drawbacks of the prior art, in particular to produce a base piece for a multi-part cartridge case that is easy and inexpensive to produce, whereby a higher retention force between the base piece and the case jacket can be achieved and / or the drawing grooves thereof can be produced with lower manufacturing tolerances.

[0006] This problem is solved by the object of the independent claims. Thus, a method for making a base piece for receiving a primer for a multi-part cartridge case is provided. It can be envisaged that the invention is used for making a base piece molded according to one of the aspects or exemplary embodiments of the invention described below. A bullet, also called a cartridge, generally comprises the following parts: a cartridge case, a primer for igniting the propellant powder, a propellant charge as an energy carrier, and a projectile that is fired from a firearm. A multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket that is rigidly connected to the base piece for receiving the projectile. When the case jacket and the base piece are attached to each other, the outer surface of the case jacket can rest in contact with the inner surface of the base piece. In other words, the base piece can at least partially receive the case jacket.

[0007] According to the invention, in the method for making the base piece, before a receptacle for the case jacket of a multi-part cartridge case for receiving a projectile is made, a drawing groove for engagement by a firearm ejector is made by molding or shaping, in particular by cold forming. The receptacle for the case jacket can also be made by molding or shaping, in particular by cold forming, and can be formed as a central recess in the base piece. The deformation is generally a non-cutting manufacturing process. In a non-cutting manufacturing process, the base piece is given a different shape without removing or adding material from the base piece. During deformation, the mass of the base piece remains the same. A cold forming process such as impact extrusion can be used to deform the drawing groove and / or the receptacle of the case jacket. Due to the characteristic hardening of the material of the base piece during deformation, the base piece has a higher strength and / or a higher hardness after deformation, at least in the deformed parts, i.e. in the part of the drawing groove and possibly in the part of the receptacle for the case jacket. Due to the higher strength and / or higher hardness, a stronger retention force can be achieved between the base piece and the case jacket and / or between the base piece and the primer, such that cartridge cases having base pieces made using the method according to the invention can withstand greater internal pressures upon firing of the projectile.

[0008] Also, since the drawing groove is deformed before the receptacle for the case jacket is produced, the drawing groove can be produced using simpler and cheaper tools. A further advantage of the method according to the invention is that the dimensional accuracy of the drawing groove during deformation is higher and more reliably ensured. This is because the tool used to deform the drawing groove does not cause surface defects in the part of the drawing groove, as occurs, for example, with the segmented tools used in the prior art. The base piece produced using the method according to the invention has a more reliable drawing function, since surface defects can have a negative effect on the drawing function. By producing the receptacle after the deformation of the drawing groove, it is ensured that the higher dimensional accuracy and the higher hardness or higher strength are not impaired by the production of the receptacle.

[0009] In an exemplary embodiment of the method according to the invention, the drawing grooves are already made before starting the production of the receptacle. In this way, it can be ensured that the dimensional accuracy of the drawing grooves and the strength and / or hardness of the base piece are ensured independently of the production of the receptacle for the case jacket and / or that they are not impaired by the simultaneous or prior production of the receptacle.

[0010] In a further exemplary embodiment of the invention, the drawn grooves are not disturbed during fabrication of the receptacle. In this way, it can be ensured that the dimensional accuracy of the drawn grooves and the strength and / or hardness of the base piece are not compromised after deformation of the drawn grooves, for example, by a segmented tool that may be used to fabricate the receptacle, which may cause surface defects or bumps in the drawn grooves that may impair the drawing function.

[0011] According to a further aspect of the present invention, which may be combined with the above-mentioned aspects and exemplary embodiments, a method for making a base piece for receiving a primer for a multi-part cartridge case is provided. The method may be envisaged for making a base piece molded according to one of the aspects or exemplary embodiments of the present invention described below. A bullet, also called a cartridge, generally comprises the following parts: a cartridge case, a primer for igniting the propellant powder, a propellant charge as an energy carrier, and a projectile that is fired from a firearm. A multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile, which is rigidly connected to the base piece.

[0012] A multi-part cartridge case generally includes at least one base piece for receiving a primer facing the primer, and a case jacket that is rigidly connected to the base piece for receiving a projectile. When the case jacket and the base piece are attached to each other, an outer surface of the case jacket may rest in contact with an inner surface of the base piece. In other words, the base piece may at least partially receive the case jacket. For example, the base piece may have a central recess that receives the case jacket.

[0013] In the method according to the invention, a withdrawal groove for engagement by a firearm ejector is produced by deformation, in particular cold forming, whereby the primer groove flank of the withdrawal groove is formed by material displacement in the longitudinal direction of the base piece without radially outwardly displacing material. The deformation is generally a non-cutting production process. In a non-cutting production process, the base piece is given a different shape without removing or adding material from the base piece. During deformation, the mass of the base piece remains the same. The primer groove flank of the extraction groove can be oriented transversely, in particular perpendicularly, to the longitudinal direction of the base piece. The firearm ejector can grip and remove the empty cartridge case after firing the projectile via the extraction groove or primer groove flank. The primer groove flank can be the most important point for a reliable extraction function. By deforming the groove flank according to the invention, the groove flank is produced directly by axial material deformation without an increase in the outer diameter of the base piece by radially outwardly displacing material during deformation of the extraction groove. In the area where the material has been displaced, the diameter of the base piece can be smaller after deformation of the drawing groove than before deformation of the drawing groove. As a result of such deformation, on the one hand the material has a characteristically higher strength and / or higher hardness, and on the other hand the deviations in strength and / or hardness are smaller. In other words, the strength and / or hardness curve in the base piece is more uniform, especially in the area of ​​the drawing groove and / or in the receptacle and / or primer for the case jacket. It can thus be more reliably guaranteed that sufficient material strength and / or material hardness is obtained to ensure the necessary holding forces between the base piece and the case jacket and / or between the base piece and the primer.A further advantage of the method according to the invention is that the groove flanks can be produced with higher dimensional accuracy, in particular that the transitions from the groove flanks to the jacket of the base piece and to the groove base adjacent to the groove flanks, which are essentially oriented in the longitudinal direction of the base piece, can always be produced in the same manner, for example as sharp shoulders by longitudinally oriented material displacements, and that the empty cartridge case can be reliably removed. In other words, the drawing groove or primer groove flank has a higher dimensional accuracy. A higher dimensional accuracy can also be more reliably guaranteed. A further advantage of the method according to the invention is that more cost-effective tools with a simpler structure can be used for producing the drawing grooves, which cannot further cause surface defects in the part of the drawing groove, in particular in the part of the groove flanks. Surface defects can impair the drawing function, as with the segmented tools used in the previous description.

[0014] In an exemplary embodiment of the invention, the creation of the drawn grooves involves a flow of material directed in the opposite direction to the forming direction, in other words there is a flow of material opposite to the direction of movement of the tool used to deform the drawn grooves, in this way it can be ensured that during deformation no material is displaced radially outwards.

[0015] According to a further exemplary embodiment of the method according to the invention, the drawn groove is first preformed such that its primer groove flank is inclined at an angle of less than 90° to the longitudinal direction of the base piece. It can be envisaged that the drawn groove is preformed using a pair of punch-dies. In this way, simpler and cheaper tools can be used, since the material does not have to be deformed as much initially.

[0016] In a further exemplary embodiment of the method according to the invention, the preformed drawing groove is further deformed by reverse extrusion. It can be envisaged that the drawing groove is further deformed by means of a second pair of punch and die. Reverse extrusion is an extrusion process in which the material flow and the punch movement direction are in opposite directions.

[0017] This means that the material flow is directed in the opposite direction to the forming direction and to the opposite direction of the movement of the forming tool. In this embodiment, the groove flanks are only oriented at an angle of 90° to the longitudinal direction of the base piece after further deformation. The two-step production of the drawn groove means that simpler and more cost-effective tools can be used for each step. It can also be envisaged to use the dies of the forming punch-die pair also in the second step to further deform the already preformed drawn groove, so as to deform the drawn groove faster and more cost-effectively.

[0018] According to a further aspect of the invention, which may be combined with the above-mentioned aspects and exemplary embodiments, a method is provided for making a base piece for receiving a primer for a multi-part cartridge case. The method may be envisaged for making a base piece molded according to one of the aspects or exemplary embodiments of the invention described below. A bullet, also called a cartridge, generally comprises the following parts: a cartridge case, a primer for igniting the propellant powder, a propellant charge as an energy carrier, and a projectile that is fired from a firearm.

[0019] A multi-part cartridge case generally includes at least one base piece for receiving a primer facing the primer, and a case jacket that is rigidly connected to the base piece for receiving a projectile. When the case jacket and the base piece are attached to each other, an outer surface of the case jacket may rest in contact with an inner surface of the base piece. In other words, the base piece may at least partially receive the case jacket. For example, the base piece may have a central recess that receives the case jacket.

[0020] According to the invention, in a method for making a base piece for receiving a primer for a multi-part cartridge case, a withdrawal groove for engagement by a firearm ejector is made by deformation, in particular cold forming, without subsequent machining. The deformation is generally a non-cutting manufacturing process. In a non-cutting manufacturing process, the base piece is given a different shape without removing or adding material from the base piece. During deformation, the mass of the base piece remains the same. It is quicker and more cost-effective, since no subsequent machining process is required after deformation of the withdrawal groove. Also, a higher and more reliable dimensional accuracy of the withdrawal groove can be guaranteed.

[0021] In an exemplary embodiment, at least one step for producing the inner and / or outer geometric shape of the base piece can be performed by punching. This significantly improves the production efficiency. In particular, the production performance is greatly improved and the production costs can be significantly reduced, in particular by approximately 30%. This makes the production of the cartridge case very suitable for mass production and / or automatic production. In an exemplary embodiment of the cartridge case, the base piece comprises an annular jacket and a through hole extending through the jacket, in particular through the receiving recess for the primer. The through hole can be at least partially produced by punching. In other words, the inner geometric shape of the base piece can be at least partially produced by punching.

[0022] According to a further aspect of the invention, which may be combined with the above-mentioned aspects and exemplary embodiments, a tool arrangement is provided for introducing an extraction groove for engagement by a firearm ejector into a case blank for making a base piece for receiving a primer for a multi-part cartridge case. The extraction groove allows the firearm ejector to grip and remove the empty cartridge case after firing a projectile. It may be envisaged to use the tool arrangement to make a base piece molded according to one of the aspects or exemplary embodiments of the invention described below. A bullet, also called a cartridge, generally comprises the following parts: a cartridge case, a primer for igniting the propellant powder, a propellant charge as an energy carrier, and a projectile that is fired from a firearm. A multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile in a rigid connection to the base piece. A multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile in a rigid connection to the base piece. When the case jacket and base piece are attached to one another, an outer surface of the case jacket may rest in contact with an inner surface of the base piece. In other words, the base piece may at least partially receive the case jacket. For example, the base piece may have a central recess that receives the case jacket.

[0023] The tool arrangement may be adapted to carry out the pressure forming process. According to the invention, the tool arrangement comprises a particularly segmented die for clamping the face side of the case blank and for engaging in the case cavity of the case blank, and a case-shaped press plunger for engaging circumferentially around the periphery of the case blank. The die and / or the press plunger may be formed to be rotationally symmetrical. The case blank may be produced in a first step, for example by setting a piece of wire or by punching it out of a plate. In a further step, a case cavity may be produced, for example by extrusion, into which the die of the tool arrangement according to the invention engages during deformation. It may be envisaged that the case cavity forms a primer receptacle on the finished base piece.

[0024] According to an aspect of the invention, the press plunger is movable relative to the die for deforming, in particular cold forming, the drawing groove. In particular, the press plunger can be movable relative to the die strictly axially, in particular in the longitudinal direction of the base piece or case blank. In other words, a purely translational movement of the press plunger can be provided for creating the drawing groove. The need for an additional radial mobility in the segmented tools used in the prior art, i.e. for the individual segments of the segmented tool to move radially relative to one another for pressing or deformation, can be dispensed with. In comparison with the tools typically used in the prior art, the tool arrangement according to the invention has a simpler structure and is therefore less expensive and less prone to errors. The tool arrangement according to the invention, and in particular the press plunger according to the invention, can be used to create the drawing groove without the generation of ridges or surface defects in the portion of the drawing groove between the individual segments of the tool. The ridges or surface defects may adversely affect the function of the firearm ejector and / or may have to be subsequently removed by machining with additional effort and additional costs. By deforming the drawing groove with the tool arrangement according to the invention, a higher strength and / or higher hardness of the base piece can also be achieved, resulting in a stronger holding force between the base piece and the case jacket and / or between the base piece and the primer. A further advantage of the tool tension arrangement according to the invention is that a more uniform hardness and / or strength curve can be achieved in the base piece.

[0025] It should be understood that the embodiments relating to the method for producing the base piece according to the invention apply equally to the tool arrangement according to the invention.

[0026] In an exemplary embodiment of the invention, the press plunger is circumferentially closed. Alternatively or additionally, the press plunger is constructed from a single piece. Such a press plunger creates the pull groove without the irregularities and surface imperfections that occur in the prior art when using segmented tools to deform the pull groove.

[0027] According to a further aspect of the invention, which may be combined with the above-mentioned aspects and exemplary embodiments, a tool arrangement is provided for introducing an extraction groove for engagement by a firearm ejector into a case blank for making a base piece for receiving a primer for a multi-part cartridge case. The extraction groove allows the firearm ejector to grip and remove the empty cartridge case after firing a projectile. It may be envisaged to use the tool arrangement to make a base piece molded according to one of the aspects or exemplary embodiments of the invention described below. A bullet, also called a cartridge, generally comprises the following parts: a cartridge case, a primer for igniting the propellant powder, a propellant charge as an energy carrier, and a projectile that is fired from a firearm. A multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile in a rigid connection to the base piece. A multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile in a rigid connection to the base piece. When the case jacket and base piece are attached to one another, an outer surface of the case jacket may rest in contact with an inner surface of the base piece. In other words, the base piece may at least partially receive the case jacket. For example, the base piece may have a central recess that receives the case jacket.

[0028] The tool arrangement may be adapted to carry out the pressure forming process. According to the invention, the tool arrangement comprises a particularly segmented die for clamping the face side of the case blank and engaging the case cavity of the case blank, and a case-shaped press plunger for gripping the outer periphery of the case blank. The die and / or the press plunger may be formed to be rotationally symmetrical. The press plunger may be formed in the case shape. The case blank may be produced in a first step, for example by setting a piece of wire or by punching it out of a plate. In a further step, a case cavity may be produced, for example by extrusion, in which the die of the tool arrangement according to the invention engages during deformation. It may be envisaged that the case cavity forms a primer receptacle on the finished base piece.

[0029] According to an aspect of the invention, the press plunger has a material displacement protrusion on its inner side facing the case blank, and during the pressing movement of the press plunger relative to the die, the tool structure forms, by means of the material displacement protrusion, a primer groove flank of the drawing groove for engagement by a firearm ejector. In particular, the pressing movement can be in a purely axial, in particular longitudinal, direction of the base piece or case blank. The material displacement protrusion can be formed in a radial, circumferential and / or planar direction, in particular without any ridges or recesses. The material displacement protrusion can be oriented at an angle of 90° or at an angle less than 90° relative to the longitudinal direction of the base piece or case blank. By means of the material displacement protrusion, a higher dimensional accuracy of the drawing groove can be achieved and it can be ensured that no ridges or surface defects occur in the portion of the drawing groove that could impair the drawing function. A further advantage of the tool arrangement according to the invention is that the extraction groove and in particular the groove flank can be produced with higher dimensional accuracy, in particular that the transitions from the groove flank on the one hand to the jacket of the base piece and to the groove base adjacent to the groove flank, which are essentially oriented in the longitudinal direction of the base piece, can always be produced in the same manner, for example as sharp shoulders due to material displacements directed in the longitudinal direction, and that the empty cartridge cases can be more reliably removed. In other words, the extraction groove or primer groove flank has a higher dimensional accuracy. The higher dimensional accuracy can also be more reliably guaranteed.

[0030] It should be understood that the embodiments relating to the method for producing the base piece according to the invention apply equally to the tool arrangement according to the invention.

[0031] In an exemplary embodiment of the tool arrangement according to the invention, the material displacement projection has a pressing surface which is inclined with respect to the pressing movement direction. The pressing movement direction may coincide with the longitudinal direction of the base piece or the case blank. In exemplary further developments, in particular the material inclination angle is in the range of 10° to 80°, in particular in the range of 15° to 75°, in particular in the range of 20° to 70° or in the range of 25° to 65°. It can be envisaged that the drawing groove is preformed by means of an inclined pressing surface and that the preformed drawing groove is then deformed.

[0032] According to a further aspect of the invention, which may be combined with the above-mentioned aspects and exemplary embodiments, a tool arrangement is provided for introducing an extraction groove for engagement by a firearm ejector into a case blank or pre-base piece for making a base piece for receiving a primer for a multi-part cartridge case. The extraction groove allows the firearm ejector to grip and remove the empty cartridge case after firing a projectile. It can be envisioned that the tool arrangement is used to make a base piece molded according to one of the aspects or exemplary embodiments of the invention described below. A bullet, also called a cartridge, generally comprises the following parts: a cartridge case, a primer for igniting the propellant powder, a propellant charge as an energy carrier, and a projectile that is fired from a firearm. A multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile in a rigid connection to the base piece. A multi-part cartridge case generally includes at least one base piece for receiving the primer facing the primer, and a case jacket that is rigidly connected to the base piece for receiving the projectile. When the case jacket and the base piece are attached to each other, an outer surface of the case jacket may rest in contact with an inner surface of the base piece. In other words, the base piece may at least partially receive the case jacket. For example, the base piece may have a central recess that receives the case jacket.

[0033] The tool arrangement may be adapted to carry out a pressure forming process. The tool arrangement further comprises a forming punch with at least two, in particular precisely two, punch parts for deforming the finished drawing groove, the punch parts being arranged to engage circumferentially around the periphery of the case blank or the pre-base piece stage. The forming punch may be adapted to displace material from the case blank or pre-base piece stage by a press movement so as to imprint or form the drawing groove. The punch parts, in particular the punch halves, may be movably mounted relative to one another and / or may be formed identically. The punch parts may grip and / or clamp, in particular cold form, the case blank or pre-base piece stage in a pliers-like manner.

[0034] Furthermore, a tool arrangement according to a further aspect of the invention comprises an anvil that is translationally movable relative to the forming punch for fixing the face side of the case blank opposite to the face side or the base piece pre-stage, and that can be in abutting contact with the forming punch. For example, the anvil can have at least one operative state and another operative state, in particular an immobile state. In the operative state, the anvil is in abutting contact with the forming punch. In the immobile state, the anvil is not in abutting contact with the forming punch. In particular, the anvil can be translated between the punch parts, in particular the punch halves.

[0035] According to a further aspect of the invention, the facing abutment contact surfaces of the forming punch and the anvil are conformal with one another, for example such that the abutment contact surfaces are self-centering during translational movement of the anvil relative to the forming punch, particularly in the engagement direction of the abutment contact.

[0036] In an exemplary embodiment of the tool arrangement according to the invention, the abutment contact surface of the forming punch is at least partially, in particular generally concave, and / or the abutment contact surface of the anvil is at least partially, in particular generally convex. At the stop contact, there can be essentially complete abutment contact. In particular, a relative movement between the abutment and the forming punch transverse to the translational movement direction of the anvil is reliably prevented. According to an exemplary further development, the abutment contact surface of the forming punch forms a concave receptacle relative to the anvil, the anvil essentially filling the receptacle completely. For example, the receptacle can have a hemispherical shape. And the anvil can have a matching shape.

[0037] In an exemplary embodiment of the tool arrangement according to the invention, the anvil comprises a central projection adjacent to the abutment contact surface, the central projection being arranged to engage a receptacle for a case jacket of a multi-part cartridge case, such that the structure of the receptacle, or the structure in which the receptacle will be subsequently made, is maintained during the creation of the withdrawal groove.

[0038] In a further exemplary embodiment of the invention, the tool arrangement is adapted to generate a recognizable separation point on the outside of the base piece having a dimension of at most 0.2 mm, in particular 0.15 mm, or about 0.1 mm. For this purpose, the punch part can displace the material of the base piece during pressing of the base piece and clamp the material between them. This results in a separation point or seam protruding from the outside of the base piece.

[0039] According to a further aspect of the invention, which may be combined with the above-mentioned aspects and exemplary embodiments, there is provided a base piece for receiving a primer for a multi-component cartridge case, produced according to a method according to the invention and / or by a tool arrangement according to the invention.

[0040] According to further aspects of the invention, which may be combined with the above-mentioned aspects and exemplary embodiments, a base piece for receiving a primer for a multi-component cartridge case is provided. The base piece may be produced according to the method according to the invention and / or by the tool arrangement according to the invention. It should be understood that the above-mentioned embodiments and advantages of the method and the tool arrangement according to the invention apply equally to the base piece according to the invention. A bullet, also called a cartridge, generally comprises the following parts: a cartridge case, a primer for igniting the propellant powder, a propellant charge as an energy carrier, and a projectile to be fired from a firearm. A multi-component cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile in a rigid connection to the base piece. A multi-component cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile in a rigid connection to the base piece. When the case jacket and the base piece are attached to each other, the outer surface of the case jacket may rest in contact with the inner surface of the base piece. In other words, the base piece can at least partially receive the case jacket. For example, the base piece can have a central recess that receives the case jacket.

[0041] The base piece comprises an annular jacket having a central priming bore and a receptacle opening into said priming bore for a case jacket of said multi-part cartridge case for receiving a projectile. The receptacle for the case jacket may open directly into the priming bore or may be separated from the priming bore by a web. In this case, a through bore may be provided in the web to fluidly connect the priming bore to the receptacle. The base piece may be rotationally symmetrically shaped and may define an axis of rotation oriented in the longitudinal direction of the base piece.

[0042] According to an embodiment of the invention, the jacket has an extraction groove for internal engagement by a firearm ejector. Via the extraction groove, the firearm ejector can grip and extract the empty cartridge case after firing a projectile. The extraction groove has a primer groove flank oriented transversely, in particular perpendicularly, to the longitudinal direction of the base piece, a groove flank opening into the primer groove flank, and a groove base oriented essentially in the longitudinal direction of the base piece. According to the invention, the hardness of the jacket at the primer groove flank deviates by less than 40% from the hardness of the jacket at the groove base. Such a hardness profile can result, for example, from the degree of deformation of the material resulting from the deformation of the extraction groove and possibly the receptacle of the case jacket. The degree of deformation is a measure of the shape change when making the base piece according to the invention.

[0043] In an exemplary embodiment of the invention, the hardness of the material can be directly dependent on, for example, the degree of deformation. Thus, the hardness profile according to the invention is characteristic of the deformation production of the drawing groove of the base piece. As a measure of the hardness of the material, for example, the Vickers hardness can be used.

[0044] In an exemplary embodiment of the invention, the hardness of the jacket at the primer groove flank deviates from the hardness of the jacket at the groove base by less than 35%. In particular, the hardness of the jacket at the primer groove flank deviates from the hardness of the jacket at the groove base by less than 30%, less than 25%, less than 20%, less than 15% or less than 10%. In an exemplary further development, the hardness of the jacket at the primer groove flank substantially corresponds to the hardness of the jacket at the groove base. Thus, in a further development, a homogeneous hardness profile of the base piece in the portion of the drawn groove is obtained.

[0045] According to a further aspect of the invention, which may be combined with the above-mentioned aspects and exemplary embodiments, there is provided a base piece for receiving a primer for a multi-part cartridge case, the base piece being capable of being produced according to a method according to the invention and / or by a tool arrangement according to the invention.

[0046] It should be understood that the above-mentioned embodiments and advantages of the method and tool arrangement according to the invention apply equally to the base piece according to the invention. A bullet, also called a cartridge, generally comprises the following parts: a cartridge case, a primer for igniting the propellant powder, a propellant charge as an energy carrier, and a projectile to be fired from a firearm. A multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile, rigidly connected to the base piece. A multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile, rigidly connected to the base piece. When the case jacket and the base piece are attached to each other, the outer surface of the case jacket can rest in contact with the inner surface of the base piece. In other words, the base piece can at least partially receive the case jacket. For example, the base piece can have a central recess for receiving the case jacket.

[0047] The base piece includes an annular jacket having a priming bore wall defining a priming bore extending therethrough and a receptacle wall opening into the priming bore wall forming a receptacle for a case jacket of the multi-part cartridge case for receiving a projectile. The base piece may be rotationally symmetrically shaped and may define an axis of rotation oriented longitudinally of the base piece.

[0048] According to the invention, the hardness of the core section of 25% to 75% of the wall thickness of the receptacle wall and / or the priming bore wall does not decrease in the longitudinal direction of the base piece from the primer-side lower surface to the projectile-side upper surface. In an exemplary further development, the hardness of the core section in particular remains constant or increases continuously. In other words, the base piece has a homogeneous hardness profile in the cross section of the priming bore wall and / or the receptacle wall between the primer-side lower surface and the projectile-side upper surface. As a measure of the hardness of a material, for example, the Vickers hardness can be used. Such a hardness profile is characteristic for the creation of a drawing groove by deformation. The hardness of a material can for example be directly dependent on the degree of deformation of the material. The degree of deformation is a measure of the shape change when creating a base piece according to the invention.

[0049] According to a further aspect of the invention, which may be combined with the above-mentioned aspects and exemplary embodiments, there is provided a base piece for receiving a primer for a multi-part cartridge case, the base piece being capable of being produced according to a method according to the invention and / or by a tool arrangement according to the invention.

[0050] It should be understood that the above-mentioned embodiments and advantages of the method and tool arrangement according to the invention apply equally to the base piece according to the invention. A bullet, also called a cartridge, generally comprises the following parts: a cartridge case, a primer for igniting the propellant powder, a propellant charge as an energy carrier, and a projectile to be fired from a firearm. A multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile, rigidly connected to the base piece. A multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile, rigidly connected to the base piece. When the case jacket and the base piece are attached to each other, the outer surface of the case jacket can rest in contact with the inner surface of the base piece. In other words, the base piece can at least partially receive the case jacket. For example, the base piece can have a central recess for receiving the case jacket.

[0051] The base piece comprises the annular jacket with a central priming bore and a receptacle opening into the priming bore, for a case jacket of the multi-part cartridge case for receiving a projectile. According to the invention, a withdrawal groove for engagement by a firearm ejector is introduced into the jacket by deformation, in particular cold forming, without machining. The withdrawal groove allows the firearm ejector to grip and remove the empty cartridge case after firing the projectile. In the prior art, the withdrawal groove had to be machined after deformation, for example by machining out the irregularities, which results in additional costs and additional effort. The deformation of the withdrawal groove can be recognized on the finished base piece due to the fact that the groove flanks are formed very planarly, since there are no surface defects or bumps in the part of the withdrawal groove, especially in the area of ​​the primer groove flank.

[0052] In an exemplary embodiment of the base piece according to the invention, the drawing groove is free of material flags in the circumferential direction. A material flag is to be understood as an unevenness or a bump in the section of the drawing groove. This occurs in the prior art when the drawing groove is made with a segmented tool. This is due to the fact that when the individual segments of the tool move relative to each other, material displaced from the base piece accumulates between them and finally remains on the base piece as a material flag in the area of ​​the seam between the two cooperating segments. The deviation of the diameter in the section of the drawing groove at the same axial height is less than 0.1 mm.

[0053] According to further aspects of the present invention that may be combined with the above-mentioned aspects and exemplary embodiments, a cartridge case for a bullet is provided. For example, the bullet has a caliber ranging from 4.6 to 12.7. The bullet, also referred to as a cartridge, generally comprises the following parts: a cartridge case, a primer for igniting the propellant powder, a propellant charge as an energy carrier, and a projectile to be fired from a firearm. The multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile in a rigid connection to the base piece. The multi-part cartridge case generally comprises at least one base piece for receiving the primer facing the primer, and a case jacket for receiving the projectile in a rigid connection to the base piece. When the case jacket and the base piece are attached to each other, an outer surface of the case jacket may rest in contact with an inner surface of the base piece. In other words, the base piece may at least partially receive the case jacket. For example, the base piece may have a central recess for receiving the case jacket.

[0054] According to the invention, the cartridge case comprises a rotationally symmetrical case jacket and a base piece according to the invention attached thereto. It can be envisaged that a primer is inserted, in particular pressed, into said base piece.

[0055] Preferred embodiments are set forth in the dependent claims.

[0056] Further characteristics, features and advantages of the present invention will become apparent from the following detailed description of preferred embodiments of the present invention, given with reference to the accompanying exemplary drawings. [Brief description of the drawings]

[0057] [Figure 1] 1 is a cross-sectional view of an exemplary embodiment of a cartridge case according to the present invention. [Diagram 2] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Diagram 3] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 4] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Diagram 5] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 6] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 7] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 8] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 9] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 10] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 11] FIG. 11 is a schematic diagram of the manufacturing sequence of the tool structure according to the present invention, shown in FIGS. [Figure 12] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 13] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 14] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 15]Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 16] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 17] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 18] Schematic diagram of a manufacturing sequence of a base piece according to the present invention. [Figure 19] 5A-5C are schematic diagrams of alternative fabrication sequences for further exemplary embodiments of a tool arrangement according to the invention; [Figure 20] 5A-5C are schematic diagrams of alternative fabrication sequences for further exemplary embodiments of a tool arrangement according to the invention; [Figure 21] 5A-5C are schematic diagrams of alternative fabrication sequences for further exemplary embodiments of a tool arrangement according to the invention; [Figure 22] 5A-5C are schematic diagrams of alternative fabrication sequences for further exemplary embodiments of a tool arrangement according to the invention; [Figure 23] 5A-5C are schematic diagrams of alternative fabrication sequences for further exemplary embodiments of a tool arrangement according to the invention; [Figure 24] 5A-5C are schematic diagrams of alternative fabrication sequences for further exemplary embodiments of a tool arrangement according to the invention; [Diagram 25] 5A-5C are schematic diagrams of alternative fabrication sequences for further exemplary embodiments of a tool arrangement according to the invention; [Figure 26] 5A-5C are schematic diagrams of alternative fabrication sequences for further exemplary embodiments of a tool arrangement according to the invention; [Figure 27] 1 is a simulation of the degree of forming of a base piece according to the prior art. [Figure 28] 4 is a simulation of the deformation degree of the base piece according to the present invention. [Figure 29] 1 is a color simulation of the degree of deformation of a base piece according to the prior art. [Diagram 30] 1 is a simulation in color of the degree of deformation of a base piece according to the invention. [Diagram 31] 1 is a perspective view of an exemplary embodiment of a tool arrangement according to the present invention; [Diagram 32] 1 is a perspective view of an exemplary embodiment of a base piece according to the present invention; [Diagram 33] 13A and 13B are perspective views of further exemplary embodiments of cartridge cases according to the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0058] In the following description of exemplary embodiments of the invention, a base piece according to the invention for a multi-component cartridge is generally designated by the reference numeral 1, a cartridge case according to the invention is generally designated by the reference numeral 10, and a tool arrangement according to the invention for producing the base piece is designated by the reference numeral 100.

[0059] Figure 1 shows an exemplary embodiment of a cartridge case 10 according to the invention in a cross-sectional view. The cartridge case 10 comprises a base piece 1 and a case jacket 3 rigidly connected thereto for receiving a projectile (not shown). In the embodiment shown in Figure 1, the base piece 1 and the case jacket 3 are rotationally symmetrically shaped. The case jacket 3 has a constant wall thickness and is, for example, shaped from metal.

[0060] The base piece 1 may likewise be made from a metal or metal alloy, for example copper, case hardened steel, or brass. The base piece 1 has a central recess 5 for receiving the case jacket 3. Opposite the recess 5, the base piece 1 has a further central cylindrical recess 7 in which a primer (not shown) is received. In the following description, the recess 5 will be referred to as the receptacle 5 and the recess 7 as the primer receptacle.

[0061] The base piece 1 also has a central priming bore 15, which is defined by the annular jacket 11 of the base piece and opens into a receptacle 5 for the case jacket 3. In the embodiment shown in FIG. 1, a web 17 is molded between the receptacle 5 and the primer receptacle 7. The primer receptacle 7 extends from the primer-side underside 19 of the base piece 1 in the direction of the projectile-side upper side 21 of the base piece 1 to the web 17. The portion of the jacket 11 which defines the primer receptacle 7 is referred to below as the priming bore wall 23. The receptacle 5 for the case jacket 3 extends from the projectile-side upper side 21 in the direction of the primer-side underside 19 of the base piece 1 to the web 17. The portion of the jacket 11 which defines the receptacle 5 for the case jacket 3 is referred to below as the receptacle wall 25. In the embodiment shown in FIG. 1, the web 17 has a central through bore 27 that fluidly connects the primer receptacle 7 and the receptacle 5. In the embodiment of FIG. 1, the priming bore 15 is thus formed by the primer receptacle 7 and the through bore 27. The web 17 may prevent the receptacle wall 25 from unintentionally separating from the priming bore wall 23 when the projectile is fired. In a further embodiment of the base piece 1 according to the invention (see FIG. 26), the receptacle 5 may open directly into the primer receptacle 7 without a web between them as shown in FIG. 1. In this embodiment, the priming bore 15 is formed only by the primer receptacle 7. In both embodiments, the case jacket 3 has a corresponding through bore 26 on the side facing the base plate 1. The purpose of this is to transmit the force generated by the primer to the projectile in order to fire it.

[0062] The base plate 1 also comprises an extraction groove, which in the following is generally designated by the reference number 9. The extraction groove 9 is introduced into the outer surface 13 of the annular jacket 11 of the base piece 1 and extends in the circumferential direction around the entire circumference of the base piece 1. The ejector of the firearm can grip and extract the empty cartridge case 10 after firing the projectile via the extraction groove 9. The extraction groove 9 comprises a primer groove flank 29 oriented essentially perpendicular to the longitudinal direction L of the base piece 1, a radially inner groove base 31 oriented essentially in the direction of the longitudinal direction L, and a transition edge 33 adjacent to the groove base 31 and inclined with respect to the longitudinal direction L. To extract the empty cartridge case 10, the ejector of the firearm engages the primer groove flank 29. This is therefore the most important point for reliable extraction. The extraction groove 9 or the groove flank 29 is free of material flags in the circumferential direction.

[0063] A material flag is an irregularity or a bump in the part of the drawn groove 9 or the groove flank 29. In the prior art, this occurs when the drawn groove is produced with a segmented tool between the individual segments of the tool. In the base piece 1 according to the invention, the dimensional precision of the drawn groove 9 is very high, since in the base piece 1 according to the invention the deviation in diameter of the parts of the drawn groove 9 at the same axial height is less than 0.1 mm. In the base piece 1 according to the invention, the groove flank 29, the groove base 31 and the transition edge 33 are therefore formed in a particularly planar manner, in particular without bumps or surface defects, so that no subsequent machining is required. Such a drawn groove 9 can be produced with the method according to the invention for introducing a drawn groove 9 into a base piece 1, which is described in detail below.

[0064] 2 to 10 show schematic diagrams of the production sequence of the method according to the invention for producing a base piece 1 according to the invention based on the individual stages of the base piece during the method.

[0065] First, a metal wire is prepared, which may be cut or trimmed to length to form a cylindrical wire section 35 (FIG. 2). The wire section 35 is then set to form a thick disk 37 (FIG. 3). A cup structure 39 having a central inner cavity 41, which may also be referred to as a case cavity, is then produced by extrusion (FIG. 4). The cup structure 39 is hereinafter referred to as a case blank 43.

[0066] The case cavity 41 is then further recessed to form the primer receptacle 7 (FIG. 5). At the same time, the drawing groove 9 is preformed by deformation. Deformation is generally a non-cutting fabrication process that gives the base piece 1 a different shape without removing or adding material from the base piece 1. The mass of the base piece 1 remains the same during deformation.

[0067] FIG. 5 shows that the preformed primer groove flank 28 of the preformed drawn groove 8 is oriented at an angle of less than 90° to the longitudinal direction L of the base piece 1 or case blank 43. The inclination angle of the preformed groove flank 28 is indicated with reference number 45 in FIG. 5. In a next step, the preformed groove flank 28 is further deformed. FIG. 6 shows the fully deformed groove flank 29 after further deformation. It can be seen that it is oriented at an angle of 90° transversely to the longitudinal direction L. This angle is indicated with reference number 47 in FIG. 6.

[0068] In the two following production steps, the desired inner and outer geometry of the base piece 1 is produced. First, the outer geometry is pre-pressed (FIG. 7), which produces the transition edge 33 of the drawing groove 9 and forms the groove base 31. In the next step, the receptacle 5 for the case jacket 3 is pressed (FIG. 8). The base piece 1 is then calibrated (FIG. 9) and the web 17 is drilled. This forms the connection 27 between the primer receptacle 7 and the receptacle 5 for the case jacket 3.

[0069] The schematic production sequence shows that in the production method according to the invention, the drawing grooves 9 are introduced and completed in the case blank 43 (FIG. 6) before the production of the receptacle 5 for the case jacket 3 starts (FIG. 8). This ensures that the high dimensional accuracy of the drawing grooves 9 achievable during deformation is not impaired by the simultaneous or prior production of the receptacle.

[0070] 11 to 18 show the manufacturing sequence of FIGS. 2 to 10 for manufacturing the base piece 1 according to the invention with the associated tools.

[0071] Figure 11 shows again the cylindrical wire section 35 of figure 2. The wire section 35 is transformed into a thick-walled disk 39 in figure 12 by means of a die 49 for fixing the wire section axially and a press plunger 51 which is movable in the longitudinal direction L. In figure 13, the upper side 53 of the thick-walled disk 39 is fixed by the press plunger 51 so that the case cavity 41 can be introduced from the lower side 55 of the thick-walled disk 39 by extrusion with a further press plunger 57.

[0072] Figure 14 shows a case blank 43 produced in the previous steps in a tool arrangement 100 according to the invention for preforming the drawing grooves 9. The tool arrangement 100 comprises a preforming punch-die pair 59 consisting of a preforming die 61 and a preforming punch 63 which are movable only in the longitudinal direction L. The pressing movement direction P and thus the forming direction U therefore run along the longitudinal direction L of the base piece 1 or of the case blank 43. The pressing movement direction P and the forming direction U are each indicated by an arrow in Figures 14 and 15.

[0073] In the exemplary manufacturing process of Figs. 11 to 18, the press plunger 51 for introducing the case cavity 41 is also used as a preforming die 61 for preforming the drawing groove 9. To preform the drawing groove 9, the preforming die 61 fixes the lower side 55 of the case blank 43 and engages with a central protuberance 65 in the case cavity 41 of the case blank 43. The central protuberance 65 centers the case blank 43 and fixes it radially. The preforming punch 63 is formed in a case-like manner and is closed in the circumferential direction. The preforming punch 63 is also made as a one-piece part and surrounds the case blank 43 on the outside. The preforming punch 63 has a material displacement protuberance 69 in the radial circumferential direction on the inner surface 67 facing the case blank 43. When the preforming punch 63 is moved in the longitudinal direction L towards the preforming die 61, the groove flank 29 of the drawing groove 9 is preformed by the material displacement protuberance 69. As shown in FIG. 5, the preformed groove flanks 28 are oriented at an angle 45 of less than 90° relative to the longitudinal direction L (see FIG. 15).

[0074] Accordingly, the material displacement protrusions 69 of the preforming punch 63 are likewise oriented at an angle of less than 90° with respect to the longitudinal direction L. In particular, the pressing surfaces 71 of the material displacement protrusions 69 may be oriented at an inclination angle with respect to the longitudinal direction L in the range of 10° to 80°, preferably in the range of 15° to 75°, in the range of 20° to 70°, or in the range of 25° to 65°.

[0075] Figure 14 shows that when the preforming punch 63 moves along the longitudinal direction L of the case blank 43 towards the preforming die 61 during preforming of the drawing grooves 9, the material is displaced only axially, i.e. along the press movement direction P or the forming direction U. No material is displaced radially outwards, as can be seen from a comparison of Figures 14 and 15 by the fact that the outer diameter of the case blank 43 does not increase during preforming of the drawing grooves 9.

[0076] FIG. 15 shows a further tool arrangement 100 according to the invention. With the further tool arrangement 100 the preformed groove flank 28 is further deformed by reverse extrusion. In the present context, reverse extrusion is to be understood as an extrusion process in which the material flow is generated in the opposite direction to the forming direction U or in the opposite direction to the movement direction of the forming tool. The tool arrangement 100 comprises a further punch-die pair 75, consisting of a die 77 and a press plunger 79. The die 77 in FIG. 15 is identical to the preforming die 61 in FIG. 14, only differing in that the central ridge 65 is higher and thus the primer receptacle 7 is already formed from the case cavity 41. For example, the central ridge 65 can be axially displaceable in the preforming die 61. This allows costs and time to be saved during production, since no additional dies are necessary for further deformation of the preformed drawing groove 8. The press plunger 79 is also formed in a case-like manner. The underside 83 of the press plunger 79 facing the case blank 43 can be considered as a material-displacement convexity originating from the inner side 81 of the press plunger 79. As the press plunger 79 moves in the longitudinal direction L towards the die 77, the material is displaced to form groove flanks 29 oriented at an angle of 90° transversely to the longitudinal direction L as shown in Figure 6. In the embodiment shown in Figure 15, the upper side 53 of the case blank 43 is additionally fixed by a further press plunger 85.

[0077] Observing simultaneously the production steps of Figure 15 and the resulting stage of the case blank 43 of Figure 16 with the fully deformed drawn groove 9, it can be seen that the deformation of the preformed groove flank 28 into the finished groove flank 29 is accompanied by a material flow against the press movement direction P and the deformation direction U, or movement of the press plunger 79 along the longitudinal axis L of the case blank 43. However, as with the preforming of the drawn groove 9, there is no radially outward material displacement.

[0078] The tool arrangement according to the invention for deforming the drawing groove 9 shown in Figures 14 and 15 has a simpler construction compared to the tools used in the prior art and is therefore more cost-effective than the tools used in the prior art.

[0079] In Fig. 16-18 the inner and outer geometric shapes of the base piece 1 are pressed. In Fig. 16 the transition edge 33 of the drawing groove 9 and the outer geometric shape of the receptacle 5 for the case jacket 3 are first pressed with a segmented tool 87. The upper side 53 of the case blank 43 remains fixed by the press plunger 85, and the lower side 55 of the case blank 43 remains fixed by the die 77. In Fig. 17 the outer geometric shape is finish pressed using a further segmented tool 89, while the inner geometric shape of the receptacle 5 is formed by the press plunger 91. The segmented tools 87, 89 may each consist of several punching segments which move radially towards each other for deformation. Finally, Fig. 18 shows the finished base piece 1. However, it is still necessary to introduce the through bore 27 into the web 17 between the receptacle 5 and the primer receptacle 7.

[0080] 11 to 18 show that the drawing groove 9 is not interfered with during the production of the receptacle 5 and that the high dimensional accuracy of the drawing groove 9 is not impaired after deformation. It is also clear that no subsequent machining steps are necessary after the deformation of the drawing groove 9. A further advantage of the production method according to the invention is that the transitions between the groove flank 29 and the groove base 31 as well as the transitions between the groove flank and the outer surface 13 of the jacket 11 of the base piece 1 can be reliably formed at an angle of 90° (see FIG. 1).

[0081] Figures 19 to 26 show an alternative production sequence for a base piece 1 according to the invention, together with the tools used for this purpose. The tools used are shown at the top of each of Figures 19 to 26, and the resulting stage of the base piece 1, i.e. the case blank 43, is shown below. The base piece 1 to be produced is shown in Figure 26. It differs from the base piece 1 of Figure 1 or Figures 10 and 18 in that no web is provided between the receptacle 5 for the case jacket 3 and the primer receptacle 7.

[0082] First, the blank 37 is punched out of a plate (FIG. 19). Alternatively, the blank 37 is pressed from a piece of wire, as shown in FIGS. 2 and 3. A central inner cavity 93 is then produced on the upper side 53 of the blank 37 by backward extrusion (FIG. 20) by a press plunger 95. This results in the formation of the cup structure 39. For this purpose, the press plunger 95 may be displaceable in the longitudinal direction L of the case blank 43 in a case shape guide 96. The lower side 55 of the blank 37 is fixed by the die 50. In the next step, the case cavity 41 is produced on the lower side 55 of the blank 37 by forward extrusion (FIG. 21) by a press plunger 97. This results in the formation of the double cup structure 40.

[0083] The case blank 43 is secured axially and radially by a press plunger 95 which remains engaged in the inner cavity 93. A web 99 remains between the case cavity 41 and the cavity 93. This is then pierced using the press plunger 95 to produce the case blank 43 shown at the bottom of FIG. 22. The underside 53 of the case blank 43 is held by a case shape die 98. The case blank 43 of FIG. 22 already has a continuous priming bore 15 through the annular jacket 11.

[0084] Analogous to the manufacturing process of figures 11 to 18, the drawing grooves 9 are first preformed by deformation in the next step (figure 23). The tool arrangement 100 according to the invention essentially corresponds to the tool arrangement 100 of figure 14. Therefore, only the differences are described below with reference to the embodiment of figures 11 to 28. In the embodiment of figure 23, the die 61 does not have a central ridge for engagement in the central inner cavity 41 of the case blank 43, because the case blank 43 already has a continuous priming bore 15 and cannot abut a web on the central ridge. Instead, the case blank 43 is centred and radially fixed by a press plunger 95 which projects completely through the priming bore 15 of the case blank 43. In the next step, the preformed drawing grooves 8 are further deformed (figure 24). The tool arrangement 100 according to the invention again essentially corresponds to the tool arrangement 100 of FIG. 15, with the difference that the case blank 43 remains centered and radially fixed by the press plunger 95. In FIG. 23, the press plunger 95 is held by a guide 96 and rests on the die 61 with one end facing the die 61. In contrast, in FIG. 24, the press plunger 95 is further displaced in the longitudinal direction L and is guided by the guide 96 and by a die 77 which is correspondingly shaped in a case-shaped manner. It should be understood that the die 61 can also be case-shaped so as to guide the press plunger 95, and that the die 77 does not necessarily have to be case-shaped, but that the press plunger 95 can be held only by the guide 96 during further deformation (FIG. 24).

[0085] The inner and outer geometric shapes of the base piece 1 are then pressed. In particular, the transition edge 33 and the groove base 33 of the drawing groove 9 (FIG. 25) and the receptacle 5 for the jacket 3 (FIG. 26) are formed by segmented tools 87, 89 and a press plunger 91. See the embodiment of the manufacturing process in FIGS. 16-18.

[0086] In an alternative manufacturing sequence, the drawing grooves 9 are similarly introduced and completed in the case blank 43 (FIG. 24) before the manufacturing of the receptacle 5 for the case jacket 3 begins (FIG. 25). It can also be seen from FIGS. 24 and 25 that the drawing grooves 9 are not disturbed during the manufacturing of the receptacle 5 and that subsequent machining of the drawing grooves 9 is not required.

[0087] Figures 27 and 28 show a direct comparison between a brass base piece 2 typical of the prior art (Figures 27 and 29) and a brass base piece 1 according to the invention (Figures 28 and 30). In Figures 27 and 29, the reference numbers for the individual elements of the base piece are each increased by 100. In the base piece 2 according to the prior art, the drawing groove 109 is made after the production of the receptacle 5 for the case jacket 3. In the base piece 1 according to the invention, the drawing groove 9 is made by deformation before the production of the receptacle 5 for the case jacket 3 by pure axial deformation of the material. In both figures, the webs 17, 117 separating the receptacle 5, 105 for the case jacket 3 and the primer receptacle 7 are not yet pierced.

[0088] As is clear from the comparison, the base piece 1 according to the invention has a higher degree of deformation. It can be seen that the receptacle wall 25 and the priming bore wall 23 of the base piece 1 according to the invention have a higher degree of deformation, especially in the part of the receptacle 5 for the case jacket 3 and in the part of the drawing groove 9. The degree of deformation is a measure of the deformation of the base piece 1. It indicates the extent to which the material is deformed when making the base piece 1 from the wire section or disk 37. A higher degree of deformation results in a higher strength and / or a higher hardness of the material. The hardness of the base piece 1 is directly dependent on the degree of shaping. A higher degree of shaping of the base piece 1 results in a higher hardness, so that a higher retention force can be achieved between the base piece 1 and the case jacket 3, as well as between the base piece 1 and the primer. As a result, the cartridge case 10 with the base piece 1 according to the invention can withstand a higher internal pressure when firing a projectile.

[0089] The base piece 1 produced using the method or tool arrangement 100 according to the invention also has a characteristic hardness profile in the jacket 11 of the base piece 1. This therefore indicates that the drawing groove 9 was produced using the method or tool arrangement 100 according to the invention.

[0090] 28 and 30 it can be seen that a uniform deformation and therefore a uniform hardness profile exists in the portion of the drawn groove 9, since the deformation of the groove flank 29 essentially corresponds to the deformation of the groove base 31. In contrast, in the case of the base piece 2 of FIG. 27 or FIG. 29 which is typical in the prior art, the deformation of the groove flank 29 is greater than the deformation of the groove base 131.

[0091] Furthermore, from the lines 101 and 103 extending along the center of the wall thickness of the priming bore walls 23, 123 and the receptacle walls 25, 125, it can be seen that the degree of deformation of the base piece 1 according to the invention increases continuously from the lower surface 19 on the primer side to the upper surface 21 on the projectile side, which is not the case for the base piece 2 of the prior art.

[0092] Fig. 31 shows a further exemplary embodiment of the tool arrangement 100 according to the invention. Fig. 31 shows a perspective view of a section of the tool arrangement 100 with the focus on the forming punch 115. In the preferred embodiment according to Fig. 31, the forming punch 115 comprises two punch halves 127, 129. These punch halves 127, 129 define a receptacle 131 between them. The receptacle 131 is circular in cross section and concave, in particular hemispherical, in the other cross section direction. Between the two punch halves 127, 129, the anvil 107 is translationally movable relative to the forming punch 115, in order to come into abutting contact with and move away from the forming punch 115 in the translation direction.

[0093] FIG. 32 shows a perspective view of an exemplary embodiment of a base piece 1 according to the invention. The base piece 1 is produced by a tool arrangement 100 in particular according to the invention with a forming punch with at least two punch parts. When the base piece 100 is produced by means of a segmented tool, a separation point or seam 133 that runs in the longitudinal direction of the base piece 1 and remains on the outer side 135 occurs as a long thin protrusion. The separation point 133 results from the material displaced when pressing the base piece 1 by the segmented tool, which is located between two punched parts and can be moved relative to each other to perform a pressing operation. In the pressing operation, the material is pressed and is visible as the seam 133. In the exemplary embodiment according to FIG. 32, the seam 133 essentially extends from the groove flank 129 to the upper side 21 of the base piece 1. However, the seam length of the seam 133 in the longitudinal direction of the base piece 1 can also be shorter, for example only extending to about half the height of the receptacle wall 25 (see also FIG. 33 for example). Furthermore, the depth or shape of the seam 133 may vary transversely to the longitudinal extension, in particular radially. In this case, the seam depth in the portion of the groove flank 29 may be significantly smaller than in the adjacent portion, in particular even to zero. This is believed to be because the groove flank 29 is pressed with a closed, for example cylindrical, tool, so that no material displacement occurs, which would lead to the formation of a seam. The seam depth may likewise decrease towards the top in the portion of the base piece 1 which receives the case jacket 3, since it can be flattened again by a calibrated die when joining the base piece 1 to the case jacket 3. This makes it less noticeable in this region.

[0094] In Fig. 33 a shorter seam 133 is shown where the base piece 1 is assembled or joined to the case jacket 3. In particular in the upper joining section 137 of the base piece 1 facing the case jacket 3 the seam 133 can be smoothed again after joining so as to be essentially invisible. Furthermore, as shown by the different line thickness in Fig. 33, the seam depth in the part of the groove flank 29 can be made less noticeable as well. This is because of the above-mentioned aspect of making the groove flank 29 with a closed tool.

[0095] This can minimize the functional defects of the seam 133, since a seam 133 on the outer surface 135 of the base piece can under certain circumstances adversely affect the loading capacity. A pronounced seam 133 in the part of the groove flank can under certain circumstances adversely affect the essential drawing performance of the drawing groove 9. By using the method according to the invention, which carefully controls and reduces the extent of the seam 133 in the neuralgic, functionally relevant sections, it is possible to avoid the defects resulting from the method known from the prior art, i.e. from pressing in the drawing groove with a segmented tool.

[0096] The features disclosed in the above description, the drawings and in the claims may be important both individually and in any combination for realizing the invention in its various embodiments. [Explanation of symbols]

[0097] 1 Base Piece 2 Base Piece (latest model) 10 Cartridge case 100 Tool components 3 Case Jacket 5, 105 receptacle 7, 107 Primer receptacle 8 Preformed drawing grooves 9, 108 Pull-out groove 11, 111 Circular jacket 13 External surface 15 Priming Bore 17, 117 Web 19, 119 Primer side lower surface 21, 121 Projectile side upper surface 23, 123 Priming bore wall 25, 125 Receptacle Wall 26 Through Bore 27 Through Bore 28 Preformed groove flanks 29 Groove Flank 31, 131 Groove base 33, 133 Transition edge 35 Cylindrical Wire Section 37 Thick Disc 39 Cup structure 40 Double cup structure 41 Case Cavity 43 Case Blank 45 angle 47 angle 49 Die (Setting) 50 Die 51 Press plunger (setting) 53 Press plunger (case cavity) 55 Top side 57 Lower side 59 A pair of preforming punches and dies 61 Preforming Die 63 Preforming punch 65 central ridge 67 Inner surface of punch 69 Material displacement convex part 71 Press surface 75 Punch and Die Pair 77 Die 79 Press Plunger 81 Punch inner surface 83 Material displacement convex part 85 Press Plunger 87 Segmented Tools 89 Segmented Tools 91 Press Plunger 93 Central recess 95 Press Plunger 96 Guide 97 Press Plunger 99 Web 101 Line 103 Line 115 Forming punch 127, 129 Punch half 131 Receptacle 133 Separation Point 135 External surface L Longitudinal U Molding direction P Press direction

Claims

1. A method for making a base piece (1) for receiving a primer for a multi-component cartridge case (10), comprising: a case jacket (3) of said multi-part cartridge case (10) having a drawing groove (9) formed therein for internal engagement by a firearm ejector before a receptacle (5) for said case jacket (3) for receiving a projectile is formed therein by molding, in particular by molding; method.

2. The drawing groove (9) is already made before starting to make the receptacle (5), The method of claim 1.

3. When making the receptacle (5), the extraction groove (9) is not engaged. The method of claim 1.

4. A method according to any one of claims 1 to 3 for producing a base piece (1) for receiving a primer for a multi-component cartridge case (10), comprising: a withdrawal groove (9) for engagement by a firearm ejector is created by deformation, whereby a primer groove flank (29) of said withdrawal groove (9) is formed by material displacement in the longitudinal direction (L) of said base piece (1) without material displacement radially outward; method.

5. The creation of the drawing grooves (9) involves a material flow in the opposite direction to the forming direction (U), The method of claim 4.

6. the drawing grooves (9) are first preformed, in particular by means of a pair of preforming punch dies (59), so that the primer groove flanks (28, 29) of the drawing grooves (8, 9) are inclined at an angle (45) of less than 90° to the longitudinal direction (L) of the base piece (1); The method of claim 5.

7. further deforming the preformed drawing groove (8) by counter-extrusion, in particular by means of a second pair of punches and dies (75); The method of claim 6.

8. A method according to one of claims 1 to 3 for producing a base piece (1) for receiving a primer for a multi-component cartridge case (10), comprising: The extraction groove (9) for engagement by the firearm ejector is created by deformation without subsequent machining operations; method.

9. 1. A tool arrangement (100) for introducing a withdrawal groove (9) for engagement by a firearm ejector into a case blank (43) for making a base piece (1) for receiving a primer for a multi-part cartridge case (10), comprising: a die (61, 77) for fixing a face side (55) of the case blank (43) and engaging with the case cavity (41) of the case blank (43); a case-shaped press plunger (63, 79) for circumferentially engaging the periphery of said case blank (43); A tool configuration (100) comprising: for the deformation and creation of the drawing groove (9), the press plunger (63, 79) is movable in particular purely axially relative to the die (61, 77); A tool configuration (100).

10. the press plunger (63, 79) is circumferentially closed and / or made in one piece; The tool construction (100) of claim 9.

11. 10. A tool arrangement (100) according to claim 9 for introducing a withdrawal groove (9) for engagement by a firearm ejector into a case blank (43) for producing a base piece (1) for receiving a primer for a multi-part cartridge case (10), comprising: a die (61, 77) for fixing a face side (55) of the case blank (43) and engaging with the case cavity (41) of the case blank (43); a press plunger (63, 79) for engaging the periphery of the outer surface of the case blank (43); A tool configuration (100) comprising: The press plunger (63, 79) has a material displacement protrusion (69, 83) on its inner surface (67, 81) facing the case blank (43), during a particularly strict axial pressing movement of the press plunger (63, 79) relative to the die (61, 77), the tool formation (100) forms, by means of the material displacement projections (69, 83), primer groove flanks (28, 29) of the extraction grooves (8, 9) for engagement by a firearm ejector; A tool configuration (100).

12. The material displacement convex portion (69) has a press surface (71) inclined with respect to the press movement direction (P), In particular, the inclination angle is in the range of 10° to 80°, in particular in the range of 15° to 75°, in particular in the range of 20° to 70°, or in the range of 25° to 65°; The tool construction (100) of claim 11.

13. 10. A tool arrangement (100), in particular as claimed in claim 9, for introducing a withdrawal groove (9) for engagement by a firearm ejector into a case blank (43) or a pre-base piece (109) for producing a base piece (1) for receiving a primer for a multi-part cartridge case (10), comprising: a die (61, 77) for fixing a face side (55) of the case blank (43) or the base piece pre-stage (109) and engaging with the case cavity (41) of the case blank (43) or the base piece pre-stage (109); a forming punch (105) comprising at least two, in particular two punch elements (109, 111) for deforming and creating the drawing grooves (9), the punch elements (109, 111) being arranged to engage circumferentially around the periphery of the case blank (43) or the pre-base piece (109); an anvil (107) that is translationally movable relative to the forming punch (105) for fixing a face side (115) opposite to the face side (55) of the case blank (43) or the base piece precursor (109), the anvil (107) being capable of abutting and contacting the forming punch (105); A tool configuration (100) comprising: The abutting contact surfaces (117, 119) of the forming punch (105) and the anvil (107) facing each other are conformal to each other. A tool configuration (100).

14. the abutment contact surface (119) of the forming punch (105) is at least partially, in particular entirely, concave; and / or the abutment contact surface (117) of the anvil (107) is at least partially, in particular entirely, convex; The tool arrangement (100) of claim 13, In particular, the abutment contact surface (119) of the forming punch (105) forms a concave receptacle (121) for the anvil (107), The anvil (107) substantially completely fills the receptacle (121); A tool configuration (100).

15. A base piece (1) for receiving a primer for a multi-component cartridge case (10), produced according to the method according to one of claims 1 to 3 and / or by means of a tool arrangement (100) according to claims 9 or 13.

16. A base piece (1) for receiving a primer for a multi-component cartridge case (10), in particular according to claim 15, comprising: an annular jacket (11) having a central priming bore (15); a receptacle (5) opening into said priming bore (15), for a case jacket (3) of said multi-component cartridge case (10) for receiving a projectile, In the base piece (1), The jacket (11) has a withdrawal groove (9) for internal engagement by a firearm ejector; the drawing groove (9) has a primer groove flank (29) oriented transversely to the longitudinal direction (L) of the base piece (1), a groove flank (29) opening into the primer groove flank (29), and a groove base (31) oriented substantially in the longitudinal direction (L) of the base piece (1), the hardness of the jacket (11) at the primer groove flank (29) deviates from the hardness of the jacket (11) at the groove base (31) by less than 40%; Base piece (1).

17. the hardness of the jacket (11) at the primer groove flank (29) deviates from the hardness of the jacket (11) at the groove base (31) by less than 35%, in particular by less than 30%, less than 25%, less than 20%, less than 15%, or less than 10%, In particular, the hardness of the jacket (11) at the primer groove flank (29) substantially matches the hardness of the jacket (11) at the groove base (31). The base piece (1) according to claim 16.

18. A base piece (1) according to claim 16, in particular for receiving a primer for a multi-component cartridge case (10) with an annular jacket (11), The annular jacket (11) has a priming bore wall (23) defining a priming bore (15) extending through the jacket (11), and a receptacle wall (25) opening into the priming bore wall (23) to form a receptacle (5) for a case jacket (3) of the multi-component cartridge case (10) for receiving a projectile. In the base piece (1), the hardness of the core section of the receptacle wall (25) and / or the priming bore wall (23) at 25% to 75% of the wall thickness does not decrease, in particular remains at least constant, or increases continuously, from the primer-side lower surface (19) to the projectile-side upper surface (21) in the longitudinal direction (L) of the base piece (1); Base piece (1).

19. A base piece (1) for receiving a primer for a multi-component cartridge case (10), in particular according to claim 15, comprising the annular jacket (11) with a central priming bore (15), and a receptacle (5) opening into the priming bore (15) for a case jacket (3) of the multi-component cartridge case (10) for receiving a projectile, a withdrawal groove (9) for engagement by a firearm ejector is introduced into said jacket (11) by deformation without subsequent machining operations; Base piece (1).

20. The drawing groove (9) is free of material flags in the circumferential direction, In particular, the deviation of the diameters in the sections of the drawing groove (9) at the same axial height is less than 0.1 mm; 20. The base piece (1) according to claim 19.

21. A cartridge case (10) for ammunition, comprising a rotationally symmetrical case jacket (3) and a base piece (1) attached thereto, the base piece (1) being shaped according to claim 15, In particular, a primer is inserted, in particular pressed into said base piece (1), Cartridge case (10).

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