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

Abstract

The present invention relates to a method for manufacturing a base piece for receiving a primer for a multi-part cartridge case, in which an extraction groove for engagement by a firearm ejector is formed before a receptacle for a case jacket of the multi-part cartridge case for receiving a projectile is formed, particularly by forming. The present invention also relates to a tool arrangement for manufacturing a base piece, a base piece, and a cartridge case.

Description

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

[0002] Multi-part cartridge cases are generally known and are subdivided into at least a base piece facing the primer, which holds the primer, and a case jacket firmly attached to the base piece, which holds the projectile. The base piece usually has an extractor groove to assist in ejecting a fired, empty cartridge case. A firearm's extractor can use this groove to move the empty cartridge case to the firearm's ejector, which then ejects the spent cartridge case.The extraction groove is formed on a circumferential wall of the annular base piece as a circumferential groove or recess, featuring a rear shoulder edge oriented essentially transversely to the longitudinal axis, a radially inner base surface oriented essentially in the longitudinal axis, and a transition edge adjoining the base surface and inclined with respect to the longitudinal axis. In the prior art, the extraction groove is currently manufactured by machining, which has proven suboptimal with regard to manufacturing costs and cost-effective mass production. In the field of one-piece cartridge case manufacturing, prior art already exists for producing the extraction groove by forming.This process utilizes so-called segmented punch-die tool assemblies, which are used to first create and complete the internal geometry for receiving the projectile and primer, and then, in a subsequent process step, to create the extraction groove on the outside. These punch-die tool assemblies cannot be readily transferred to multi-part cartridge cases.

[0003] For example, FR 1113479 discloses a three-piece cartridge case consisting of a base with an extractor groove, a shell, and a fastening element. Another multi-piece case is known from US 2019 / 0226817, in which the base also includes an extractor groove. Further multi-piece cartridge cases are described in the following publications: WO 2020 / 214136 A1 discloses a firearm cartridge case for withstanding high deflagration pressure. US 2015 / 241183 A1 discloses a formed, high-strength cartridge case consisting of a base and a shell, made of polymer, for blank cartridges and subsonic ammunition. EP 2 789 411 A1 discloses a method for manufacturing a cartridge case with a base and a shell, as well as a transfer press for carrying out the method. A precision-forged cartridge case is known from US 2015 / 174643 A1.

[0004] The inventors of the present invention have identified significant potential for improvement with regard to the extractor groove, namely firstly with regard to manufacturing tolerances and secondly with regard to the achievable holding forces for joining the base and case body. It has been found that it cannot always be reliably ensured that, in multi-part cartridge cases, the holding force of the base and case body will withstand the considerable forces involved in firing a firearm. Neither machining nor existing cold-forming solutions for manufacturing the extractor groove reliably achieve the desired manufacturing tolerances.Particularly when using segmented tools to produce the extraction groove, it has proven to be a significant disadvantage that the segmented tools can create surface defects in the area of ​​the extraction groove, which have a detrimental effect on the extraction function.

[0005] One object of the present invention is to overcome the disadvantages of the prior art, in particular to create a base piece for a multi-part cartridge case that is easy and inexpensive to manufacture, by means of which higher holding forces between the base piece and the case shell can be achieved and / or whose extraction groove can be manufactured with lower manufacturing tolerances.

[0006] The problem is solved by the subject matter of the independent claims.

[0007] A method for manufacturing a base for receiving a primer for a multi-part cartridge case is provided. The method may be used to produce a base designed according to one of the aspects or exemplary embodiments of the present invention described below. Ammunition, also called a cartridge, generally consists of the following components: a cartridge case; a primer for igniting the propellant powder; a propellant charge as an energy source; and a projectile to be fired from a firearm. Multi-part cartridge cases generally comprise at least one base facing the primer for receiving the primer and a case jacket firmly connected to the base for receiving the projectile.When the case jacket and base are joined, an outer surface of the case jacket can rest against an inner surface of the base; in other words, the base can at least partially accommodate the case jacket.

[0008] According to the invention, in the method for manufacturing a base piece, an extractor groove for engagement by a firearm ejector is formed, in particular by cold forming, before a receptacle for the case shell of the multi-part cartridge case is formed to receive a projectile. The receptacle for the case shell can also be formed, in particular by cold forming, and can, for example, be designed as a central recess in the base piece. Forming is generally a chipless manufacturing process in which the base piece is brought into a different shape without removing or adding material to it. The mass of the base piece remains the same during forming. A cold forming process, for example, extrusion, can be used to form the extractor groove and / or the receptacle for the case shell.During forming, the material of the base characteristically hardens, so that after forming, the base exhibits higher strength and / or higher hardness, at least in the formed areas, i.e., in the area of ​​the extractor groove and, optionally, in the area of ​​the receptacle for the case jacket. This higher strength and / or higher hardness allows for greater retention forces between the base and the case jacket and / or between the base and the primer. As a result, a cartridge case with a base produced using the inventive method can withstand higher internal pressures when the projectile is fired. Furthermore, because the extractor groove is formed before the receptacle for the case jacket is formed, simpler and less expensive tools can be used to produce the extractor groove.A further advantage of the method according to the invention is that the dimensional accuracy of the extraction groove is higher during forming and can be ensured more reliably because the tools used to form the extraction groove do not create surface defects in the area of ​​the extraction groove, such as those that can occur, for example, with segmented tools used in the prior art. These surface defects can have a negative impact on the extraction function, so that a base piece produced using the method according to the invention has a more reliable extraction function. Furthermore, by manufacturing the receptacle after forming the extraction groove, it can be ensured that the high dimensional accuracy and the higher hardness or strength are not compromised by the manufacturing of the receptacle.

[0009] In an exemplary embodiment of the method according to the invention, the extraction groove is already completed before the manufacturing of the receptacle begins. In this way, it can be ensured that the dimensional accuracy of the extraction groove and the strength and / or hardness of the base piece are guaranteed independently of the manufacturing of the receptacle for the cartridge case and / or are not affected by simultaneous or prior manufacturing of the receptacle.

[0010] In a further exemplary embodiment of the present invention, the extraction groove is not accessed during the manufacturing of the holder. This ensures that the dimensional accuracy of the extraction groove and the strength and / or hardness of the base are not impaired after forming the extraction groove, for example, by segmented tools that can be used to manufacture the holder and that can create surface defects or protrusions in the extraction groove that could impair the extraction function.

[0011] According to a further aspect of the present invention, which can be combined with the preceding aspects and exemplary embodiments, a method for manufacturing a base for receiving a primer for a multi-part cartridge case is provided. It can be provided that the method produces a base designed according to one of the aspects or exemplary embodiments of the present invention described below. Ammunition, also referred to as a cartridge, generally consists of the following components: a cartridge case; a primer for igniting the propellant powder; a propellant charge as an energy source; and a projectile to be fired from a firearm. Multi-part cartridge cases generally comprise at least one base facing the primer for receiving the primer and a case jacket firmly connected to the base for receiving the projectile.When the cartridge case and base are joined, an outer surface of the case can rest against an inner surface of the base; in other words, the base can at least partially accommodate the cartridge case. For example, the base may have a central recess to receive the cartridge case.

[0012] According to the invention, in this method, an extractor groove for engagement by a firearm ejector is formed, in particular by cold forming, such that a primer-side groove flank of the extractor groove is shaped by material displacement directed longitudinally along the base, without any material being displaced radially outwards. Forming is generally a chipless manufacturing process in which the base is reshaped without removing or adding material. The mass of the base remains constant during forming. The primer-side groove flank of the extractor groove can be oriented transversely, in particular perpendicularly, to the longitudinal direction of the base. The firearm ejector can grasp and eject the empty cartridge case after firing the projectile by means of the extractor groove or the primer-side groove flank.The groove flank on the primer side can be the most important point for a reliable extraction function. According to the invention, the groove flank is formed directly by axial material deformation, without the outer diameter of the base increasing due to radial outward material displacement during the forming of the extraction groove. In the areas where material is displaced, the diameter of the base can be smaller after forming the extraction groove than before.This type of forming process characteristically results in the material exhibiting, on the one hand, higher strength and / or higher hardness, and on the other hand, smaller deviations in strength and / or hardness. In other words, the strength and / or hardness profile in the base is more homogeneous, particularly in the area of ​​the extraction groove and / or in the area where the case jacket and / or primer are located. This allows for a more reliable assurance that sufficient material strength and / or hardness is present to guarantee the necessary holding forces between the base and the case jacket and / or between the base and the primer.A further advantage of the method according to the invention is that the groove flank can be manufactured with greater precision, and in particular the transition from the groove flank on the one hand to a surface of the base piece and on the other hand to a groove base adjacent to the groove flank, oriented essentially longitudinally along the base piece, can always be produced uniformly, for example as a sharp-edged step, due to the longitudinal material displacement, thus ensuring reliable ejection of the empty cartridge case. In other words, the extraction groove or the groove flank on the primer side exhibits higher dimensional accuracy, and this higher dimensional accuracy can also be ensured more reliably.A further advantage of the method according to the invention is that more cost-effective tools with a simpler design can be used to produce the extraction groove, which, unlike the segmented tools used in the prior art, do not produce surface defects in the area of ​​the extraction groove, in particular in the area of ​​the groove flank, which can impair the extraction function.

[0013] In an exemplary embodiment of the present invention, the production of the extraction groove involves a material flow directed against the forming direction. In other words, the material flow is contrary to the direction of movement of a tool used to form the extraction groove. This ensures that the material does not displace radially outwards during forming.

[0014] According to a further exemplary embodiment of a method according to the invention, the extraction groove is first pre-formed such that a percussion cap-side groove flank of the extraction groove is inclined at an angle of less than 90° with respect to the longitudinal direction of the base piece. It can be provided that the extraction groove is pre-formed using a pre-forming punch-die pair. In this way, the material initially requires less deformation, so that simpler and more cost-effective tools can be used.

[0015] In another exemplary embodiment of a method according to the invention, the pre-formed extraction groove is further formed by means of reverse extrusion. It can be provided that the extraction groove is further formed by means of a second punch-die pair. Reverse extrusion is understood to be an extrusion process in which the material flow and the direction of punch movement are opposite. Thus, a material flow is directed against the forming direction and against the movement of the forming tool. In this embodiment, the groove flank is only oriented at an angle of 90° transverse to the longitudinal direction of the base piece after further forming. Due to the two-stage production of the extraction groove, simpler and more cost-effective tools can be used for the individual steps.It may also be provided that the die of the preforming punch-die pair is also used for the second step to further form the already preformed withdrawal groove, in order to be able to form the withdrawal groove faster and more cost-effectively.

[0016] According to a further aspect of the present invention, which can be combined with the preceding aspects and exemplary embodiments, a method for manufacturing a base for receiving a primer for a multi-part cartridge case is provided. It can be provided that the method produces a base designed according to one of the aspects or exemplary embodiments of the present invention described below. Ammunition, also referred to as a cartridge, generally consists of the following components: a cartridge case; a primer for igniting the propellant powder; a propellant charge as an energy source; and a projectile to be fired from a firearm. Multi-part cartridge cases generally comprise at least one base facing the primer for receiving the primer and a case jacket firmly connected to the base for receiving the projectile.When the cartridge case and base are joined, an outer surface of the case can rest against an inner surface of the base; in other words, the base can at least partially accommodate the cartridge case. For example, the base may have a central recess to receive the cartridge case.

[0017] According to the invention, the method involves forming an extraction groove for gripping a firearm ejector, particularly by cold forming, without any subsequent machining. Forming is generally a chipless manufacturing process in which the base is reshaped without removing or adding material. The mass of the base remains constant during forming. Because no machining is required after forming the extraction groove, the method according to the invention is simpler, faster, and more cost-effective. Furthermore, it ensures higher and more reliable dimensional accuracy of the extraction groove.

[0018] In an exemplary embodiment, at least one manufacturing step for producing the internal and / or external geometry of the base can be performed by stamping. This significantly increases manufacturing efficiency. In particular, production output can be greatly improved, resulting in a substantial reduction in manufacturing costs, especially by approximately 30%. This makes the production of the cartridge cases considerably more suitable for mass and / or automated manufacturing. In an exemplary embodiment of the cartridge case, the base comprises an annular jacket and a through-hole extending through the jacket, specifically a receiving recess for the primer. The through-hole can be produced, at least partially, by stamping. In other words, the internal geometry of the base can be produced, at least partially, by stamping.

[0019] According to a further aspect of the present invention, which can be combined with the preceding aspects and exemplary embodiments, a tool arrangement is provided for introducing an extractor groove into a cartridge case blank for the purpose of producing a base for receiving a primer for a multi-part cartridge case. The extractor groove allows the firearm ejector to grasp and eject the empty cartridge case after the projectile has been fired. It can be provided that the tool arrangement is used to produce a base designed according to one of the aspects or exemplary embodiments of the present invention described below.Ammunition, also known as a cartridge, generally consists of the following components: a cartridge case; a primer for igniting the propellant powder; a propellant charge as the energy source; and a projectile, which is fired from a firearm. Multi-part cartridge cases typically include at least a breech end, which faces the primer, and a jacket, which is firmly attached to the breech end, to hold the projectile. When the jacket and breech end are joined, an outer surface of the jacket may rest against an inner surface of the breech end; in other words, the breech end may at least partially accommodate the jacket. For example, the breech end may have a central recess to receive the jacket.

[0020] The tool arrangement can be configured to perform a pressure forming process. According to the invention, the tool arrangement comprises a die, in particular a segmented die, for fixing an end face of the cartridge case blank and for engaging a cartridge case cavity of the cartridge case blank, and a cartridge case-shaped press punch for circumferentially gripping the cartridge case blank. The die and / or the press punch can be rotationally symmetrical. The cartridge case blank can, for example, be produced in a first step by inserting a wire segment or by punching it out from a sheet. In a further step, the cartridge case cavity, into which the die of the tool arrangement according to the invention engages during forming, can be produced, for example, by extrusion. It can be provided that the cartridge case cavity forms the primer receptacle on the finished base piece.

[0021] According to the present invention, the press punch is movable relative to the die for forming, particularly cold forming, the extraction groove. Specifically, the press punch can be moved purely axially, particularly in the longitudinal direction of the base or sleeve blank, relative to the die. In other words, a purely translational movement of the press punch can be provided for forming the extraction groove. The additional radial movement required for segmented tools used in the prior art, where individual segments of the segmented tool move radially towards each other for pressing or forming, is eliminated. Compared to tools commonly used in the prior art, the tool arrangement according to the invention has a simpler design and is therefore more cost-effective and less prone to defects.Furthermore, the tool arrangement according to the invention, and in particular the press die according to the invention, allows the extraction groove to be produced without creating protrusions or surface defects between the individual segments of the tool in the area of ​​the extraction groove. These defects could have a detrimental effect on the function of the firearm ejector and / or require subsequent removal by machining, which incurs additional effort and costs. Forming the extraction groove with the tool arrangement according to the invention also allows for higher strength and / or higher hardness of the base, resulting in higher retention forces between the base and the cartridge case and / or between the base and the primer. A further advantage of a tool arrangement according to the invention is that a more homogeneous hardness and / or strength profile can be achieved in the base.

[0022] It is clear that the statements made in relation to a method according to the invention for producing a bottom piece apply analogously to the tool arrangement according to the invention.

[0023] In an exemplary embodiment of the present invention, the press die is completely enclosed. Alternatively or additionally, the press die is manufactured from a single piece. Such a press die eliminates unevenness or surface defects during the production of the extraction groove, unlike the prior art methods for using segmented tools to form the extraction groove.

[0024] According to a further aspect of the present invention, which can be combined with the preceding aspects and exemplary embodiments, a tool arrangement is provided for introducing an extractor groove into a cartridge case blank for the purpose of producing a base for receiving a primer for a multi-part cartridge case. The extractor groove allows the firearm ejector to grasp and eject the empty cartridge case after the projectile has been fired. It can be provided that the tool arrangement is used to produce a base designed according to one of the aspects or exemplary embodiments of the present invention described below.Ammunition, also known as a cartridge, generally consists of the following components: a cartridge case; a primer for igniting the propellant powder; a propellant charge as the energy source; and a projectile, which is fired from a firearm. Multi-part cartridge cases typically include at least a breech end, which faces the primer, and a jacket, which is firmly attached to the breech end, to hold the projectile. When the jacket and breech end are joined, an outer surface of the jacket may rest against an inner surface of the breech end; in other words, the breech end may at least partially enclose the jacket. For example, the breech end may have a central depression.

[0025] The tool arrangement can be configured to perform a pressure forming process. According to the invention, the tool arrangement comprises a die for fixing an end face of the cartridge case blank and for engaging a cartridge case cavity of the cartridge case blank, and a press punch for gripping the cartridge case blank from the outside. The die and / or the press punch can be rotationally symmetrical. The press punch can be cartridge case-shaped. The cartridge case blank can be produced, for example, in a first step by inserting a wire or by punching it out of a sheet. In a further step, the cartridge case cavity into which the die of the tool arrangement according to the invention engages during forming can be produced, for example, by extrusion. It can be provided that the cartridge case cavity forms the primer receptacle on the finished base piece.

[0026] According to the present invention, the press die has a material displacement projection on its inner surface facing the cartridge case blank. During a pressing movement of the press die relative to the die, this projection forms a primer-side groove flank of the extractor groove for engagement by a firearm ejector. In particular, the pressing movement can be purely axial, especially in the longitudinal direction of the base or cartridge case blank. The material displacement projection can be radially circumferential and / or flat, especially without protrusions or depressions. The material displacement projection can be oriented at an angle of 90° or less than 90° with respect to the longitudinal direction of the base or cartridge case blank.The material displacement projection allows for higher dimensional accuracy of the extraction groove and ensures that no protrusions or surface defects occur in the extraction groove area that could impair the extraction function. Furthermore, it ensures that the material is not displaced radially outwards during forming. Another advantage of the tool arrangement according to the invention is that the extraction groove, and in particular the groove flank, can be manufactured with greater precision. Specifically, the transition from the groove flank to the surface of the base piece on the one hand, and to a groove base adjacent to the groove flank and oriented essentially longitudinally along the base piece on the other, can always be produced uniformly, for example, as a sharp-edged step, due to the longitudinal material displacement. This allows for more reliable ejection of the empty cartridge case.In other words, the extraction groove or the groove flank on the primer side has a higher dimensional accuracy, and this higher dimensional accuracy can also be ensured more reliably.

[0027] It is clear that the statements made in relation to a method according to the invention for producing a bottom piece apply analogously to the tool arrangement according to the invention.

[0028] In an exemplary embodiment of a tool arrangement according to the invention, the material displacement projection has a pressing surface inclined relative to the direction of the pressing movement. The direction of the pressing movement can coincide with the longitudinal direction of the base piece or the sleeve blank. In an exemplary further development, the angle of inclination of the material displacement projection is in the range of 10° to 80°, particularly in the range of 15° to 75°, especially in the range of 20° to 70°, or in the range of 25° to 65°. It can be provided that the extraction groove is pre-formed with the inclined pressing surface and the pre-formed extraction groove is then further formed.

[0029] According to a further aspect of the present invention, which can be combined with the preceding aspects and exemplary embodiments, a tool arrangement is provided for introducing an extractor groove into a cartridge case blank or into a breechblock pre-stage for manufacturing a breechblock for receiving a primer for a multi-part cartridge case. The extractor groove allows the firearm ejector to grasp and eject the empty cartridge case after the projectile has been fired. It can be provided that the tool arrangement is used to produce a breechblock designed according to one of the aspects or exemplary embodiments of the present invention described below.Ammunition, also known as a cartridge, generally consists of the following components: a cartridge case; a primer for igniting the propellant powder; a propellant charge as the energy source; and a projectile, which is fired from a firearm. Multi-part cartridge cases typically include at least a breech end, which faces the primer, and a jacket, which is firmly attached to the breech end, to hold the projectile. When the jacket and breech end are joined, an outer surface of the jacket may rest against an inner surface of the breech end; in other words, the breech end may at least partially accommodate the jacket. For example, the breech end may have a central recess to receive the jacket.

[0030] The tool arrangement can be configured to perform a pressure forming process. The tool arrangement further comprises a forming die made of at least two, in particular exactly two, die parts for forming the finished extractor groove, which are designed to fully grip the cartridge case blank or the head pre-stage. The forming die can be configured to displace material from the cartridge case blank or the head pre-stage by means of a pressing motion in order to imprint or form the structure of the extractor groove. The die parts, in particular the die halves, can be movably mounted relative to each other and / or be identical in design. The die parts can grip and / or clamp the cartridge case blank or the head pre-stage in a pincer-like manner, in particular by cold forming.

[0031] Furthermore, according to a further aspect of the invention, the tool arrangement comprises an anvil that is movable translationally relative to the forming die for fixing an end face opposite the end face of the sleeve blank or the base piece pre-stage, and which can be brought into a stop contact with the forming die. For example, the anvil can have at least one operating state in which it is brought into a stop contact with the forming die, and another operating state, in particular a passive state, in which it is removed from the stop contact with the forming die. In particular, the anvil can move translationally between the die parts, especially the die halves.

[0032] According to a further aspect of the invention, the opposing contact surfaces of the forming die and the anvil are shaped to match each other. For example, the contact surfaces can be shaped to match each other in such a way that self-centering occurs when the anvil is moved translationally relative to the forming die, particularly in the direction of making contact.

[0033] In an exemplary embodiment of the tool arrangement according to the invention, the stop contact surface of the forming die is at least partially, and in particular completely, concave, and / or the stop contact surface of the anvil is at least partially, and in particular completely, convex. When the stop contact is established, a substantially full-surface contact can exist, whereby it is ensured in particular that relative movement between the stop and the forming die transverse to the translational direction of movement of the anvil is prevented. According to an exemplary further development, the stop contact surface of the forming die forms a concave recess for the anvil, and the anvil substantially completely fills this recess. For example, the recess can have a hemispherical shape, and the anvil a shape adapted to it.

[0034] In an exemplary embodiment of the tool arrangement according to the invention, the anvil comprises a central projection adjoining the stop contact surface, which is designed to engage in the receptacle for the sleeve jacket of the multi-part cartridge case in order to maintain the structure of the receptacle or of the structure from which the receptacle is to be subsequently produced when forming the extraction groove.

[0035] In a further exemplary embodiment of the present invention, the tool arrangement is configured to generate a recognizable separation point with a dimension of up to 0.2 mm, in particular 0.15 mm or approximately 0.1 mm, on the outside of the base piece. For this purpose, the punch parts can displace material from the base piece during pressing and become wedged between themselves, resulting in a separation or seam point protruding from the outside of the base piece.

[0036] According to a further aspect of the present invention, which can be combined with the preceding aspects and exemplary embodiments, a base piece for receiving a primer for a multi-part cartridge case is provided, which is produced using a method according to the invention and / or with a tool arrangement according to the invention.

[0037] According to a further aspect of the present invention, which can be combined with the preceding aspects and exemplary embodiments, a base piece for receiving a primer for a multi-part cartridge case is provided. The base piece can be manufactured using a method and / or a tool arrangement according to the invention. It should be understood that the foregoing embodiments and advantages of methods and tool arrangements according to the invention apply analogously to a base piece according to the invention. Ammunition, also referred to as a cartridge, generally consists of the following components: a cartridge case; a primer for igniting the propellant powder; a propellant charge as an energy carrier; and a projectile, which is to be fired from a firearm.Multi-part cartridge cases typically comprise at least a base section facing the primer to hold the primer and a case jacket firmly attached to the base section to hold the projectile. When the case jacket and base section are joined, an outer surface of the case jacket can rest against an inner surface of the base section; in other words, the base section can at least partially accommodate the case jacket. For example, the base section may have a central recess to receive the case jacket.

[0038] The base comprises an annular mantle with a central primer hole and a receptacle opening into the primer hole for a shell casing of the multi-part cartridge case to receive a projectile. The shell casing receptacle can open directly into the primer hole or be separated from it by a rib. In the latter case, a through-hole can be provided in the rib to fluidically connect the primer hole to the receptacle. The base can be rotationally symmetrical and define an axis of rotation oriented longitudinally along the base.

[0039] According to the present invention, the casing has an extractor groove for the insertion of a firearm ejector. The extractor groove allows the firearm ejector to grasp and eject the empty cartridge case after the projectile has been fired. The extractor groove has a primer-side groove flank oriented transversely, and in particular perpendicularly, to the longitudinal direction of the base, and a groove base oriented substantially longitudinally to the primer-side groove flank. According to the invention, the hardness of the casing at the primer-side groove flank differs from the hardness of the casing at the groove base by less than 40%. Such a hardness profile can be achieved, for example, by forming the extractor groove and, optionally, the receptacle for the casing, and the resulting degree of deformation of the material.The degree of deformation refers to the measure of the change in shape during the manufacture of the base piece according to the invention. The hardness of the material can, for example, depend directly on the degree of deformation. A hardness profile according to the invention is therefore characteristic of a forming process for manufacturing the extraction groove of the base piece. The Vickers hardness test, for example, can be used as a measure of the material's hardness.

[0040] In an exemplary embodiment of the present invention, the hardness of the casing at the percussion cap-side groove flank deviates from the hardness of the casing at the groove base by less than 35%. In particular, the hardness of the casing at the percussion cap-side groove flank deviates from the hardness of the casing at the groove base by less than 30%, less than 25%, less than 20%, less than 15%, or less than 10%. InIn an exemplary further development, the hardness of the casing at the percussion cap-side groove flank essentially corresponds to the hardness of the casing at the groove base. Thus, in this further development, there is a homogeneous hardness profile of the base piece in the area of ​​the extraction groove.

[0041] According to a further aspect of the present invention, which can be combined with the preceding aspects and exemplary embodiments, a base piece for receiving a primer for a multi-part cartridge case is provided. The base piece can be manufactured using a method and / or a tool arrangement according to the invention. It should be understood that the foregoing embodiments and advantages of methods and tool arrangements according to the invention apply analogously to a base piece according to the invention. Ammunition, also referred to as a cartridge, generally consists of the following components: a cartridge case; a primer for igniting the propellant powder; a propellant charge as an energy carrier; and a projectile, which is to be fired from a firearm.Multi-part cartridge cases typically comprise at least a base section facing the primer to hold the primer and a case jacket firmly attached to the base section to hold the projectile. When the case jacket and base section are joined, an outer surface of the case jacket can rest against an inner surface of the base section; in other words, the base section can at least partially accommodate the case jacket. For example, the base section may have a central recess to receive the case jacket.

[0042] The base piece comprises an annular mantle, which has a primer wall defining a primer bore extending through the mantle and a receiving wall opening into the primer bore wall, forming a receptacle for a shell casing of the multi-part cartridge case to receive a projectile. The base piece can be rotationally symmetrical and define an axis of rotation oriented longitudinally along the base piece. According to the invention, the hardness of a core region comprising 25% to 75% of the wall thickness of the receiving wall and / or the primer bore wall does not decrease longitudinally from a primer-side underside of the base piece to a projectile-side top side. In an exemplary embodiment, the hardness of the core region remains at least constant or increases continuously.In other words, the base piece exhibits a homogeneous hardness profile in the core area of ​​the primer hole wall and / or the receiving wall between the primer-side underside and the projectile-side upper side. The Vickers hardness, for example, can be used as a measure of the material's hardness. Such a hardness profile is characteristic of a forming process used to manufacture the extraction groove. The material's hardness can, for example, depend directly on the degree of deformation. The degree of deformation refers to the measure of the change in shape during the manufacture of the base piece according to the invention.

[0043] According to a further aspect of the present invention, which can be combined with the preceding aspects and exemplary embodiments, a base piece for receiving a primer for a multi-part cartridge case is provided. The base piece can be manufactured using a method and / or a tool arrangement according to the invention. It should be understood that the foregoing embodiments and advantages of methods and tool arrangements according to the invention apply analogously to a base piece according to the invention. Ammunition, also referred to as a cartridge, generally consists of the following components: a cartridge case; a primer for igniting the propellant powder; a propellant charge as an energy carrier; and a projectile, which is to be fired from a firearm.Multi-part cartridge cases typically comprise at least a base section facing the primer to hold the primer and a case jacket firmly attached to the base section to hold the projectile. When the case jacket and base section are joined, an outer surface of the case jacket can rest against an inner surface of the base section; in other words, the base section can at least partially accommodate the case jacket. For example, the base section may have a central recess to receive the case jacket.

[0044] The base comprises an annular mantle with a central primer hole and a receptacle opening into the primer hole for a cartridge case shell of the multi-part cartridge case to receive a projectile. According to the invention, an extractor groove for the engagement of a firearm ejector is formed into the mantle, preferably by cold forming, without any subsequent machining. The extractor groove allows the firearm ejector to grasp and eject the empty cartridge case after the projectile has been fired. In the prior art, the extractor groove must be machined after forming, for example by turning down any irregularities, which incurs additional costs and effort.The forming manufacturing of the extraction groove can be recognized on the finished base piece by the fact that there are no surface defects or protrusions in the area of ​​the extraction groove and especially in the area of ​​a percussion cap-side groove flank, and the groove flank is therefore particularly flat.

[0045] In an exemplary embodiment of a base piece according to the invention, the extraction groove is free of material flaps in the circumferential direction. Material flaps are understood to be irregularities or protrusions in the area of ​​the extraction groove, which, in the prior art, arise when manufacturing the extraction groove with segmented tools because, as the individual segments of the tools move towards each other, material from the base piece displaced between them accumulates and ultimately remains on the base piece as a material flap in the area of ​​the joint between two cooperating segments. A deviation in diameter in the area of ​​the extraction groove at the same axial height can be less than 0.1 mm.

[0046] According to a further aspect of the present invention, which can be combined with the preceding aspects and exemplary embodiments, a cartridge case for ammunition is provided. For example, the ammunition has a caliber in the range of 4.6 to 12.7. Ammunition, also referred to as a cartridge, generally consists of the following components: a cartridge case; a primer for igniting the propellant powder; a propellant charge as an energy source; and a projectile to be fired from a firearm. Multi-part cartridge cases generally comprise at least a base section facing the primer for receiving the primer and a case jacket firmly connected to the base section for receiving the projectile.When the cartridge case and base are joined, an outer surface of the case can rest against an inner surface of the base; in other words, the base can at least partially accommodate the cartridge case. For example, the base may have a central depression.

[0047] According to the invention, the cartridge case comprises a rotationally symmetrical casing and a base piece according to the invention attached thereto. It may be provided that a primer is inserted, in particular pressed into, the base piece.

[0048] Preferred embodiments are specified in the dependent claims.

[0049] Further properties, features and advantages of the invention will be clarified below by describing preferred embodiments of the invention with reference to the accompanying exemplary drawings, which show: Fig. 1: a sectional view of an exemplary embodiment of a cartridge case according to the invention; Figs. 2 to 10: a schematic representation of a manufacturing process of a base piece according to the invention; Figs. 11 to 18: a schematic representation of the manufacturing process from the Figures 2 to 10in a tool arrangement according to the invention; Figs. 19 to 26: a schematic representation of an alternative manufacturing process in a further exemplary embodiment of a tool arrangement according to the invention; Fig. 27: a simulation of the degree of forming of a base piece according to the prior art; Fig. 28: a simulation of the degree of forming of a base piece according to the invention; Fig. 29: a simulation of the degree of forming of a base piece according to the prior art in color representation; Fig. 30: a simulation of the degree of forming of a base piece according to the invention in color representation; Fig. 31: a perspective view of an exemplary embodiment of a tool arrangement according to the invention; Fig. 32: an exemplary embodiment in perspective view of a base piece according to the invention; and Fig. 33: a perspective view of a further exemplary embodiment of a cartridge case according to the invention.

[0050] In the following description of exemplary embodiments of the present invention, a base piece according to the invention for a multi-part cartridge case is generally designated by reference numeral 1, a cartridge case according to the invention is generally designated by reference numeral 10, and a tool arrangement according to the invention for manufacturing a base piece is designated by reference numeral 100.

[0051] Figure 1 Figure 1 shows an exemplary embodiment of a cartridge case 10 according to the invention in a sectional view. The cartridge case 10 consists of a base 1 and a sleeve 3 firmly connected to it for receiving a projectile (not shown). In the embodiment shown in Figure 1The base piece 1 and the sleeve shell 3 are rotationally symmetrical. The sleeve shell 3 has a constant wall thickness and can, for example, be made of metal. The base piece 1 can also be made of metal or a metal alloy, such as copper, case-hardened steel, or brass.

[0052] The base piece 1 has a central recess 5 for receiving the cartridge case 3. Opposite the recess 5, the base piece 1 has another central cylindrical recess 7 in which a primer (not shown) is received. In the following description, the recess 5 is referred to as the receptacle 5 and the recess 7 as the primer receptacle 7.

[0053] The base piece 1 also has a central ignition bore 15, which is bounded by an annular mantle 11 of the base piece and opens into the receptacle 5 for the cartridge case jacket 3. In the embodiment in Figure 1A rib 17 is formed between the receptacle 5 and the primer receptacle 7. The primer receptacle 7 extends from a primer-side underside 19 of the base 1 towards a projectile-side upper surface 21 of the base 1 to the rib 17. The portion of the jacket 11 that borders the primer receptacle 7 is hereinafter referred to as the primer hole wall 23. The receptacle 5 for the case jacket 3 extends from the projectile-side upper surface 21 towards the primer-side underside 19 of the base 1 to the rib 17. The portion of the jacket 11 that borders the receptacle 5 for the case jacket 3 is hereinafter referred to as the receptacle wall 25. In the embodiment in Figure 1 The bridge 17 has a central through-bore 27 that fluidly connects the percussion cap receptacle 7 and the receptacle 5. In the embodiment in Figure 1The ignition bore 15 is thus formed by the percussion cap receptacle 7 and the through bore 27.

[0054] The bridge 17 prevents unintentional separation of the receiving wall 25 from the ignition bore wall 23 during firing of the projectile. In a further embodiment of a base piece 1 according to the invention (compare Figure 26 ) the intake 5 can lead directly into the primer intake 7, without any intermediate step as in Figure 1 A bridge is provided. In this design, the ignition bore 15 is formed only by the primer receptacle 7. In both designs, the cartridge case 3 has a corresponding through-hole 26 on a side facing the base 1 in order to transfer the force generated by the primer to the projectile for firing.

[0055] The base 1 also includes an extractor groove, which is generally referred to below as reference numeral 9. The extractor groove 9 is formed in an outer surface 13 of the annular mantle 11 of the base 1 and completely encircles the base 1. A firearm ejector can use the extractor groove 9 to grasp and eject the empty cartridge case 10 after the projectile has been fired. The extractor groove 9 comprises a primer-side groove flank 29, which is oriented substantially perpendicular to the longitudinal direction L of the base 1, a radially inner groove base 31, which is oriented substantially in the longitudinal direction L, and a transition edge 33 adjoining the groove base 31 and inclined with respect to the longitudinal direction L. To eject an empty cartridge case 10, the firearm ejector engages the groove flank 29, which is therefore the most important point for reliable ejection. The extraction groove 9 orThe groove flank 29 is free of material burrs in the circumferential direction. Material burrs are defined as irregularities or protrusions in the area of ​​the extraction groove 9 or the groove flank 29, which, in the prior art, occur between the individual segments of the tool when manufacturing the extraction groove with segmented tools. A deviation in the diameter in the area of ​​the extraction groove 9 at the same axial height is less than 0.1 mm in a base piece 1 according to the invention; the dimensional accuracy of the extraction groove 9 is therefore particularly high in a base piece 1 according to the invention. The groove flank 29, the groove base 31, and the transition edge 33 are thus particularly flat in a base piece 1 according to the invention, especially without protrusions or surface defects, so that no machining is necessary.Such an extraction groove 9 can be produced by a method according to the invention for introducing an extraction groove 9 into a base piece 1, which is explained in detail below.

[0056] The Figures 2 to 10 show a schematic representation of a manufacturing process of an inventive method for producing a bottom piece 1 according to the invention, based on the individual stages of the bottom piece 1 during the method.

[0057] First, a metal wire can be provided and cut or shortened to a specific length, resulting in a cylindrical wire section 35 ( Figure 2 ). Subsequently, the wire section 35 is set to form a thick-walled disc 37 ( Figure 3 ). Subsequently, a cup structure 39 with a central inner cavity 41, which can also be referred to as a sleeve cavity, is produced by means of extrusion ( Figure 4The cup structure 39 is referred to below as the sleeve blank 43.

[0058] The cartridge case cavity 41 is then deepened further and forms the primer receptacle 7 ( Figure 5 ). Simultaneously, the extraction groove 9 is pre-formed by forming. Forming is generally a chipless manufacturing process in which the base piece 1 is brought into a different shape without removing or adding material to the base piece 1; the mass of the base piece 1 remains the same during forming. Figure 5 It can be seen that the pre-formed primer-side groove flank 28 of the pre-formed extraction groove 8 is oriented at an angle of less than 90° with respect to the longitudinal direction L of the base piece 1 or the cartridge case blank 43. The angle of inclination of the pre-formed groove flank 28 is in Figure 5 indicated by the reference numeral 45. In the next step, the pre-formed groove flank 28 is further shaped. In Figure 6A fully formed groove flank 29 is shown after further forming. It can be seen that it is oriented at an angle of 90° transverse to the longitudinal direction L, which is Figure 6 as indicated by reference number 47.

[0059] In the following two manufacturing steps, the desired inner and outer geometry of the base piece 1 is produced. First, the outer geometry is pre-pressed ( Figure 7 ). In this process, the transition edge 33 of the extraction groove 9 is manufactured, which also forms the groove base 31. In the next step, the receptacle 5 for the case jacket 3 is pressed ( Figure 8 ). The bottom piece 1 is then calibrated ( Figure 9 ) and the bridge 17 is perforated, so that a connection 27 is created between the primer receptacle 7 and the receptacle 5 for the shell casing 3.

[0060] The schematic manufacturing process illustrates that in the manufacturing process according to the invention, the extraction groove 9 is introduced into the sleeve blank 43 and completed ( Figure 6 ) before the production of the receptacle 5 for the shell casing 3 begins ( Figure 8 This ensures that the high dimensional accuracy of the extraction groove 9 achievable during forming is not affected by simultaneous or prior manufacturing of the holder.

[0061] The Figures 11 to 18 show the manufacturing process from the Figures 2 to 10 for manufacturing a base piece 1 according to the invention with the associated tools.

[0062] Figure 11 shows again the cylindrical wire section 35 from Figure 2 This will be in Figure 12 The wire section 35 is formed into a thick-walled disc 39 using a die 49 for axially fixing it and a press punch 51 movable in the longitudinal direction L. Figure 13A top surface 53 of the thick-walled disc 39 is fixed by the press punch 51, so that the sleeve cavity 41 can be introduced from the bottom surface 55 of the thick-walled disc 39 with another press punch 57 by means of extrusion.

[0063] In Figure 14 The sleeve blank 43 produced by the previous steps is shown in a tool arrangement 100 according to the invention for preforming the extraction groove 9. The tool arrangement 100 comprises a preforming punch-die pair 59 consisting of a preforming die 61 and a preforming press punch 63 movable exclusively in the longitudinal direction L. The pressing direction P and thus the forming direction U therefore run along the longitudinal direction L of the base piece 1 or the sleeve blank 43. The pressing direction P and the forming direction U are shown in the Figure 14 and 15 Each indicated by arrows.

[0064] In the exemplary manufacturing process in the Figures 11 to 18The press die 51, used to create the case cavity 41, also serves as a preforming die 61 for preforming the extraction groove 9. For preforming the extraction groove 9, the preforming die 61 secures the underside 55 of the case blank 43 and engages the case cavity 41 of the case blank 43 with a central projection 65. The central projection 65 centers the case blank 43 and secures it radially. The preforming press die 63 is sleeve-shaped and completely enclosed. It is also manufactured in one piece and surrounds the case blank 43 on its outer side. The preforming press die 63 has a radially circumferential material displacement projection 69 on its inner surface 67 facing the case blank 43. When the preforming press punch 63 is moved in the longitudinal direction L towards the preforming die 61, a groove flank 29 of the withdrawal groove 9 is preformed by means of the material displacement projection 69.The pre-formed groove flank 28 is as in . Figure 5 shown oriented at an angle of 45° of less than 90° with respect to the longitudinal direction L (see Figure 15 Accordingly, the material displacement projection 69 of the preforming die 63 is also oriented at an angle of less than 90° with respect to the longitudinal direction L. In particular, a pressing surface 71 of the material displacement projection 69 can be oriented at an angle of inclination 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° with respect to the longitudinal direction L.

[0065] In Figure 14It can be seen that during the preforming of the extraction groove 9, the material is displaced only in the axial direction, i.e., along the pressing direction P or the forming direction U, when the preforming press punch 63 moves along the longitudinal direction L of the sleeve blank 43 towards the preforming die 61. No material displacement occurs radially outwards, which is evident from a comparison of Figure 14 and Figure 15 This can be seen from the fact that the outer diameter of the sleeve blank 43 does not increase during the pre-forming of the extraction groove 9.

[0066] In Figure 15A further tool arrangement 100 according to the invention is shown, with which the preformed groove flank 28 is further formed by means of reverse extrusion. Reverse extrusion is understood to be an extrusion process in which a material flow occurs opposite to the forming direction U or opposite to the direction of movement of the forming tool. The tool arrangement 100 comprises a further punch-die pair 75 consisting of a die 77 and a punch 79. The die 77 in Figure 15 is the same as the preforming die 61 in Figure 14with the sole difference that the central elevation 65 is higher, and thus the primer receptacle 7 has already been formed from the case cavity 41. For example, the central elevation 65 can be displaceable axially within the preforming die 61, so that no additional die is needed for further forming the preformed extraction groove 8, thus saving costs and time in manufacturing. The press punch 79 is also case-shaped, with the underside 83 of the press punch 79 facing the case blank 43 being considered a material displacement projection, starting from an inner surface 81 of the press punch 79. When the press punch 79 moves longitudinally L towards the die 77, material is displaced, resulting in a groove flank 29, which, as in Figure 6 is oriented at an angle of 90° transverse to the longitudinal direction L. The upper surface 53 of the sleeve blank 43 is in the version in Figure 15additionally fixed by another press die 85.

[0067] When considering the manufacturing step in Figure 15 and the resulting stage of the cartridge case blank 43 in Figure 16 With the fully formed extraction groove 9, it can be seen that during the forming of the preformed groove flank 28 to the finished groove flank 29, a material flow occurs in the opposite direction to the pressing movement P and the forming direction U, or the movement of the press punch 79 along the longitudinal axis L of the sleeve blank 43. As with the preforming of the extraction groove 9, however, there is no radial displacement of material.

[0068] The in the Figure 14 and 15 The tool arrangements according to the invention for forming the extraction groove 9 shown have a simpler design compared to tools used in the prior art and are therefore more cost-effective than tools used in the prior art.

[0069] In the Figures 16 to 18 The inner and outer geometry of the base piece 1 are then pressed. Figure 16 First, the transition edge 33 of the extraction groove 9 and the outer geometry of the receptacle 5 for the case jacket 3 are pressed with a segmented tool 87, with the upper surface 53 of the case blank 43 continuing to be fixed by the press punch 85 and the lower surface 55 of the case blank 43 continuing to be fixed by the die 77. Figure 17 The outer geometry is pressed to completion using another segmented tool 89, while simultaneously the inner geometry of the receptacle 5 is formed by a press punch 91. The segmented tools 87, 89 can each consist of several punch segments that move radially towards each other for forming. Figure 18Finally, a finished base piece 1 is shown, in which only the through hole 27 needs to be inserted into the bridge 17 between the receptacle 5 and the percussion cap receptacle 7.

[0070] From the Figures 11 to 18 It is evident that the extraction groove 9 is not engaged during the manufacturing of the holder 5, so that the high dimensional accuracy of the extraction groove 9 is not impaired after forming. Furthermore, it is clear that no machining is required after forming the extraction groove 9. A further advantage of the manufacturing process according to the invention is that the transition between the groove flank 29 and the groove base 31, as well as the transition between the groove flank and the outer surface 13 of the sleeve 11 of the base piece 1, can be reliably formed at an angle of 90° (compare Figure 1 ).

[0071] In the Figures 19 to 26An alternative manufacturing process for a base piece 1 according to the invention is shown, including the tools used for this purpose, wherein in the Figures 19 to 26 The tool used is shown at the top, and the resulting stage of the base piece 1 or the sleeve blank 43 is shown below. A finished base piece 1 is shown in Figure 26 depicted and differs from the bottom piece 1 in Figure 1 or the Figures 10 and 18 by the fact that no bridge is provided between the receptacle 5 for the cartridge case 3 and the primer receptacle 7.

[0072] First, a circuit board 37 is punched out from a plate ( Figure 19 Alternatively, board 37 can also be used as shown in Figures 2 and 3 depicted being pressed from a piece of wire. Subsequently, a central inner cavity 93 is formed on a top surface 53 of the circuit board 37 by means of reverse extrusion ( Figure 20) is produced by a press punch 95, so that a cup structure 39 is formed. The press punch 95 can be displaceable in a sleeve-shaped guide 96 in the longitudinal direction L of the sleeve blank 43. A bottom surface 55 of the blank 37 is fixed by a die 50. In the next step, a sleeve cavity 41 is formed on the bottom surface 55 of the blank 37 by means of forward extrusion ( Figure 21 ) is produced by a press punch 97, creating a double cup structure 40. The case blank 43 is fixed axially and radially by the press punch 95, which continues to engage in the inner cavity 93. A rib 99 remains between the case cavity 41 and the cavity 93, which is then pierced by the press punch 95 to produce a case blank 43, which is in Figure 22 as shown below. The underside 53 of the sleeve blank 43 is held by a sleeve-shaped die 98. The sleeve blank 43 in Figure 22already has a continuous ignition bore 15 through the annular casing 11.

[0073] As with the manufacturing process in the Figures 11 to 18 In the next step, a withdrawal groove 9 is pre-formed by forming ( Figure 23 The tool arrangement 100 according to the invention essentially corresponds to the tool arrangement 100 in Figure 14 , so that the explanations regarding the Figures 11 to 28 Reference is made to the above, and only the differences will be explained below. The die 61, when executed in Figure 23There is no central raised section for engaging the central inner cavity 41 of the cartridge case blank 43, because the cartridge case blank 43 already has a through-hole 15 and therefore cannot rest on a central raised section with its land. Instead, the cartridge case blank 43 is centered and radially fixed by the press 95, which extends completely through the flash hole 15 of the cartridge case blank 43. In the next step, the pre-formed extractor groove 8 is further formed ( Figure 24 The tool arrangement 100 according to the invention essentially corresponds to the tool arrangement 100 from Figure 15 with the difference that the sleeve blank 43 continues to be centered and radially fixed by the press die 95. In Figure 23 The press punch 95 is held by the guide 96 and rests on the die 61 with one end facing the die 61. Figure 24In contrast, the press punch 95 is further displaced in the longitudinal direction L and is guided by the guide 96 and the die 77, which is accordingly designed in a sleeve shape. It should be clear that the die 61 can also be designed in a sleeve shape to guide the press punch 95, and that the die 77 does not necessarily have to be sleeve-shaped; it is also possible that the press punch 95 will be shaped in a sleeve shape during further forming ( Figure 24 ) is only held by the 96 leadership.

[0074] Subsequently, the inner and outer geometry of the base piece 1 are pressed, in particular the transition edge 33 and the groove base 33 of the extraction groove 9 ( Figure 25 ) and the receptacle 5 for the shell casing 3 ( Figure 26 ), are formed by segmented tools 87, 89 and a press die 91, with reference to the descriptions of the manufacturing process in the Figures 16 to 18 is referred.

[0075] In the alternative manufacturing process, the extraction groove 9 is also introduced into the cartridge case blank 43 and completed ( Figure 24 ) before the production of the receptacle 5 for the shell casing 3 begins ( Figure 25 ). From the Figures 24 and 25 It is also evident that no access to the extraction groove 9 is involved in the production of the holder 5 and that no machining of the extraction groove 9 is necessary.

[0076] The Figures 27 and 28 show a direct comparison between a standard brass base piece 2 ( Figure 27 or 29) and a base piece 1 according to the invention made of brass ( Figure 28 or 30). In Figure 27In the figures 29 and 29, the reference numerals for the individual elements of the base are each increased by 100. In the base 2 according to the prior art, the extraction groove 109 was produced after the manufacturing of the receptacle 5 for the cartridge case 3, and in the base 1 according to the invention, the extraction groove 9 was produced by forming the material before the manufacturing of the receptacle 5 for the cartridge case 3 by means of purely axial material forming. In both figures, the web 17, 117, which separates the receptacle 5, 105 for the cartridge case 3 and the primer receptacle 7, 107 from each other, is not yet perforated.

[0077] The comparison clearly shows that the base piece 1 according to the invention has a higher degree of deformation. Particularly in the area of ​​the receptacle 5 for the cartridge case 3 and in the area of ​​the extraction groove 9, it is evident that the receiving wall 25 and the primer hole wall 23 of the base piece 1 according to the invention exhibit a higher degree of deformation. The degree of deformation is a measure of the change in shape of the base piece 1. It indicates how much the material is deformed when manufacturing a base piece 1 from a wire section 35 or a disc 37. A higher degree of deformation leads to higher strength and / or higher hardness of the material. The hardness of the base piece 1 depends directly on the degree of deformation. Due to the higher degree of deformation and the resulting higher hardness of the base piece 1, higher holding forces can be achieved between the base piece 1 and the cartridge case 3, as well as between the base piece 1 and the primer.This allows a cartridge case 10 with a base piece 1 according to the invention to withstand higher internal pressures when the projectile is fired.

[0078] A bottom piece 1 according to the invention, which was manufactured using a method or a tool arrangement 100 according to the invention, also has a characteristic hardness profile in the shell 11 of the bottom piece 1, which thus suggests that the extraction groove 9 was manufactured using the method or tool arrangement 100 according to the invention.

[0079] In Figure 28 or 30, it can be seen that the degree of deformation on the groove flank 29 essentially corresponds to the degree of deformation on the groove base 31, and thus a homogeneous degree of deformation and therefore a homogeneous hardness profile exists in the area of ​​the extraction groove 9. With a conventional base piece 2 in the prior art Figure 27In contrast, the degree of deformation at the groove flank 29 is greater than the degree of deformation at the groove base 131.

[0080] Furthermore, it can be seen from the lines 101 and 103, which run along the middle of the wall thickness of the ignition bore wall 23, 123 and the receiving wall 25, 125, that the degree of deformation in the base piece 1 according to the invention increases continuously from the primer-side underside 19 to the projectile-side top side 21, which is not the case in the base piece 2 according to the prior art.

[0081] In Figure 31 Another exemplary embodiment of a tool arrangement 100 according to the invention is shown, and the Figure 31 a perspective view of a section of the tool arrangement 100 with focus on the forming die 115, which in the preferred embodiment according to Figure 31The forming die consists of two die halves 127, 129, which define a receptacle 131 between them that is round in cross-section and concave, in particular semi-spherical, in the other cross-sectional direction. An anvil 107 is movable translationally between the two die halves 127, 129 relative to the forming die 115, in order to be able to come into contact with the forming die 115 and to be moved away from the forming die 115 in a translational direction. Figure 32Figure 1 shows an exemplary embodiment of a bottom piece 1 according to the invention in a perspective view. This bottom piece is produced using a tool arrangement 100, particularly according to the invention, which comprises a forming die made of at least two die parts. When the bottom piece 100 is manufactured using the segmented tool, a separation or seam 133 extends along the longitudinal axis of the bottom piece 1 and remains on the outer surface 135, forming a narrow, elongated projection. The separation 133 results from the material displaced during pressing of the bottom piece 1 using the segmented tool. This material is located between the two die parts that move towards each other to perform the pressing motion, where it is compressed and is visible as the seam 133. In the exemplary embodiment according to Figure 1, the material is... Figure 32The seam 133 extends essentially from the groove flank 129 to the upper surface 21 of the bottom piece 1. However, the seam length of the seam 133 in the longitudinal direction of the bottom piece 1 can also be shorter and, for example, extend only to about half the height of the receiving wall 25 (see also, for example, Figure 33Furthermore, the depth or extent of the weld 133 can vary transversely to its longitudinal extent, particularly in the radial direction. The weld depth in the area of ​​the groove flank 29 can be significantly less, in particular negligible, than in the adjacent sections. This can be attributed to the fact that the groove flanks 29 are pressed with a closed, for example cylindrical, tool, so that no material displacement occurs that would result in weld formation. The weld depth can also decrease again towards the top of the upper section of the base piece 1, which receives the sleeve 3, because it can be leveled out again during the joining of the base piece 1 to the sleeve 3 and by means of a calibration die, so that it is less pronounced in this area.

[0082] A varying, shorter seam 133 is in Figure 33The figure shows a base piece 1 combined with a sleeve 3, or joined together. In particular, in the area of ​​an upper joining section 137 of the base piece 1 facing the sleeve 3, the seam 133 can be smoothed out again after joining, so that it is essentially not visible. Furthermore, as shown in the Figure 33As indicated by the varying line thickness, the seam depth in the area of ​​the groove flank 29 is less pronounced, which is due to the previously described aspect of manufacturing the groove flank 29 using a closed tool. This also minimizes any potential functional disadvantages of the seam 133. A seam 133 on the outer surface 135 of the base piece could potentially have a negative impact on the loading capacity. A pronounced seam 133 in the area of ​​the groove flank could potentially have a negative impact on the essential extraction function of the extraction groove 9. With the method according to the invention, in which the extent of the seam 133 is deliberately controlled and reduced at the critical, function-relevant sections, the disadvantages of methods known from the prior art, namely pressing extraction grooves with segmented tools, can be avoided.

[0083] The features disclosed in the foregoing description, figures and claims can be important for the realization of the invention in its various embodiments, both individually and in any combination. REFERENCE MARK LIST

[0084] 1 Base piece 2 Base piece (state of the art) 10 Cartridge case 100 Tool arrangement 3 Case mantle 5,105 Receptacle 7,107 Primer receptacle 8 Pre-formed extraction groove 9,109 Extraction groove 11,111 Annular mantle 13 Outer side 15 Primer bore 17,117 Web 19,119 Primer-side underside 21,121 Projectile-side upper side 23,123 Primer bore wall 25,125 Receptacle wall 26 Through hole 27 Through hole 28 Pre-formed groove flank 29 Groove flank 31,131 Groove base 33,133 Transition edge 35 Cylindrical wire section 37 Thick-walled disc 39 Cup structure 40 Double cup structure 41 Sleeve cavity 43 Sleeve blank 45 Angle 47 Angle 49 Die (setting) 50 Die 51 Punch (setting) 53 Punch (sleeve cavity) 55 Top 57 Bottom 59 Preform punch-die pair 61 Preform die 63 Preform punch 65 Central rise 67 Punch inside 69 Material displacement projection 71 Pressing surface 75 Punch-die pair 77 Die 79 Punch 81 Punch inside 83 Material displacement projection 85 Punch 87 Segmented tool 89 Segmented tool 91 Punch 93 Central recess 95 Press punch 96 Guide 97 Press punch 99 Web 101 Line 103 Line 115 Forming punch 127, 129 Punch half 131 Recording 133 Separating point 135 Outside L Longitudinal direction U Forming direction P Press movement direction,

Claims

1. Method for manufacturing a base piece (1) designed in particular according to one of claims 15 to 20 for receiving a primer for a multi-part cartridge case (10), in which an extraction groove (9) for engagement by a firearm ejector is formed before a receptacle (5) for a shell (3) of the multi-part cartridge case (10) for receiving a projectile is formed in particular.

2. Method according to claim 1, wherein the extraction groove (9) is already completed before the manufacture of the receptacle (5) begins, and / or wherein the extraction groove (9) is not accessed during the manufacture of the receptacle (5).

3. Method, in particular according to one of claims 1 to 2, for manufacturing a base piece (1) designed in particular according to one of claims 13 to 17 for receiving a primer for a multi-part cartridge case (10), in which an extraction groove (9) for engagement by a firearm ejector is manufactured by forming such that a primer-side groove flank (29) of the extraction groove (9) is formed by a displacement of material directed in the longitudinal direction (L) of the base piece (1), without material being displaced radially outwards.

4. Method according to claim 3, wherein the production of the extraction groove (9) involves a material flow directed against the forming direction (U), wherein in particular the extraction groove (9) is first preformed, in particular by means of a preforming punch-die pair (59), such that a percussion cap-side groove flank (28, 29) of the extraction groove (8, 9) is inclined at an angle (45) of less than 90° with respect to the longitudinal direction (L) of the base piece (1), wherein in particular the preformed extraction groove (8) is further formed, in particular by means of a second punch-die pair (75), by means of reverse extrusion.

5. Method, in particular according to one of the preceding claims, for producing a base piece (1) designed in particular according to one of claims 13 to 17 for receiving a primer for a multi-part cartridge case (10), in which an extraction groove (9) for engagement by a firearm ejector is formed and manufactured without machining.

6. Tool arrangement (100) for introducing an extractor groove (9) for engagement by a firearm ejector into a cartridge case blank (43) for producing a base piece (1) designed in particular according to one of claims 13 to 17 for receiving a primer for a multi-part cartridge case (10), comprising a die (61, 77) for fixing an end face (55) of the cartridge case blank (43) and for engaging a cartridge case cavity (41) of the cartridge case blank (43) and a cartridge case-shaped press punch (63, 79) for circumferentially gripping the cartridge case blank (43), wherein the press punch (63, 79) is movable in particular purely axially relative to the die (61, 77) for forming the extractor groove (9).

7. Tool arrangement (100) according to claim 6, wherein the press punch (63, 79) is fully enclosed and / or made from a single piece.

8. Tool arrangement (100), in particular according to one of claims 6 to 7, for introducing an extraction groove (9) for engagement by a firearm ejector into a cartridge case blank (43) for producing a base piece (1), in particular designed according to one of claims 13 to 17, for receiving a primer for a multi-part cartridge case (10), comprising a die (61, 77) for fixing an end face (55) of the cartridge case blank (43) and for engaging a cartridge case cavity (41) of the cartridge case blank (43) and a press punch (63, 79) for externally gripping the cartridge case blank (43), wherein the press punch (63, 79) has a material displacement projection (69, 83) on its inner side (67, 81) facing the cartridge case blank (43), by means of which, in a particularly purely axial pressing movement of the Pressing die (63, 79) relative to the die (61, 77) the tool arrangement (100) a percussion cap-side groove flank (28, 29) of the extraction groove (8,9) shaped to allow access by a firearm ejector.

9. Tool arrangement (100) according to claim 8, wherein the material displacement projection (69) has a pressing surface (71) inclined relative to the direction of pressing movement (P), wherein in particular an angle of inclination 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°.

10. Tool arrangement (100), in particular according to one of claims 6 to 9, for introducing an extractor groove (9) for engagement by a firearm ejector into a cartridge case blank (43) or into a base piece pre-stage (109) for producing a base piece (1), in particular designed according to one of claims 13 to 21, for receiving a primer for a multi-part cartridge case (10), comprising a die (61, 77) for fixing an end face (55) of the cartridge case blank (43) or the base piece pre-stage (109) and for engaging a cartridge case cavity (41) of the cartridge case blank (43) or the base piece pre-stage (109), and a forming die (105) made of at least two, in particular exactly two, die parts (109, 111) for forming the extractor groove (9), which is designed for the circumferential designed to grip the sleeve blank (43) or the base piece pre-stage (109),and an anvil (107) that is movable translationally relative to the forming die (105) for fixing one of the end faces (115) opposite the end face (55) of the sleeve blank (43) or the base piece pre-stage (109), which can be brought into a stop contact with the forming die (105), wherein the opposing stop contact surfaces (117, 119) of the forming die (105) and the anvil (107) are shaped to match each other.

11. Tool arrangement (100) according to claim 10, wherein the stop contact surface (119) of the forming die (105) is at least partially, in particular completely, concave and / or the stop contact surface (117) of the anvil (107) is at least partially, in particular completely, convex, wherein in particular the stop contact surface (119) of the forming die (105) forms a concave recess (121) for the anvil (107) and the anvil (107) substantially completely fills the recess (121).

12. Base piece (1) for receiving a primer for a multi-part cartridge case (10), which is manufactured according to the method according to one of claims 1 to 5 and / or by means of the tool arrangement (100) according to one of claims 6 to 11.

13. Base piece (1), in particular according to claim 12, for receiving a primer for a multi-part cartridge case (10), comprising an annular jacket (11) with a central ignition bore (15) and a receptacle (5) opening into the ignition bore (15) for a case jacket (3) of the multi-part cartridge case (10) for receiving a projectile, wherein the jacket (11) has an extraction groove (9) for engagement by a firearm ejector, which has a primer-side groove flank (29) oriented transversely to the longitudinal direction (L) of the base piece (1) and a groove base (31) opening into the primer-side groove flank (29) and oriented substantially in the longitudinal direction (L) of the base piece (1), wherein the hardness of the jacket (11) at the primer-side groove flank (29) differs from the hardness of the Mantels (11) deviates at the groove base (31) by less than 40%.

14. Base piece (1) according to claim 13, wherein the hardness of the jacket (11) at the percussion cap side groove flank (29) differs 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%, wherein in particular the hardness of the jacket (11) at the percussion cap side groove flank (29) corresponds substantially to the hardness of the jacket (11) at the groove base (31).

15. Base piece (1), in particular according to claim 13 or 14, for receiving a primer for a multi-part cartridge case (10), comprising an annular mantle (11) which has a primer hole wall (23) defining a primer hole (15) extending through the mantle (11) and a receiving wall (25) opening into the primer hole wall (23) and forming a receptacle (5) for a case mantle (3) of the multi-part cartridge case (10) for receiving a projectile, wherein the hardness of a core region of 25% to 75% of the wall thickness of the receiving wall (25) and / or the primer hole wall (23) does not decrease in the longitudinal direction (L) of the base piece (1) from a primer-side underside (19) to a projectile-side top side (21), in particular remains at least constant or increases continuously.

16. Base piece (1), in particular according to one of claims 13 to 15, for receiving a primer for a multi-part cartridge case (10), comprising an annular mantle (11) with a central ignition bore (15) and a receptacle (5) opening into the ignition bore (15) for a case mantle (3) of the multi-part cartridge case (10) for receiving a projectile, wherein an extraction groove (9) for engagement by a firearm ejector is formed into the mantle (11) without machining.

17. Bottom piece (1) according to claim 16, wherein the extraction groove (9) is free of material flaps in the circumferential direction, wherein in particular a deviation of the diameter in the area of ​​the extraction groove (9) at the same axial height is less than 0.1 mm.

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