LEAD-FREE CARTRIDGE COMPONENT AND CARTRIDGE COMPRISING SAME

Abstract

An offensive charge intended for the manufacture of a cartridge for firing with a firearm does not contain lead. It is made of multiple projectiles (10), in which the projectiles are formed of at least two substantially spherical pellets (5) connected to one another by a metal connecting wire (6) of fixed predetermined length, the pellets being made of an alloy containing tin and antimony. A cartridge containing such projectiles, and a method for the mass-production of these lead-free projectiles are also described.

Claims

1. An offensive charge intended to manufacture a cartridge for shooting with a firearm made up of multiple projectiles (10) formed by at least two substantially spherical pellets (5) connected to one another by a metal connecting wire (6) with a fixed predetermined length, wherein said pellets are made from an alloy comprising tin and antimony.

2. The offensive charge according to claim 1, wherein the alloy of the pellets (5) is 99% made up of tin and antimony.

3. The offensive charge according to claim 1, wherein the alloy of the pellets (5) comprises from 90% to 98% tin.

4. The offensive charge according to claim 1, wherein the alloy of the pellets (5) comprises from 2% to 10% antimony.

5. The offensive charge according to claim 1, wherein the alloy of the pellets (5) further comprises no more than 1% of a third metal.

6. The offensive charge according to claim 1, wherein the alloy (5) is made up of 94.5% tin, 5% antimony and 0.5% copper.

7. The offensive charge according to claim 1, wherein the connecting wire (6) between two pellets (5) is a brass wire with a length comprised between 0.5 mm and 10 mm.

8. The offensive charge according to claim 1, wherein the projectile (10) comprises two connected pellets (5) with a diameter smaller than or equal to 4 mm.

9. A cartridge for shooting with a firearm, comprising a cartridge case (1) in which a propulsive charge (2) and an offensive charge (3) are found separated by a wad (4), wherein said offensive charge is according to claim 1.

10. The cartridge according to claim 9, wherein the offensive charge contains between 50 and 200 projectiles (10), formed by pellets (5) connected in pairs.

11. A method for manufacturing an offensive charge according to claim 1, which comprises the following steps: pouring the alloy containing tin and antimony into a polymer matrix, comprising two separable molds, i.e., an upper one including a central orifice and a lower one (11), between which an array of branched channels (13) is arranged extending along a substantially radial orientation from said central upper orifice and each ending with a spherical cavity (14), separating the molds and recovering the clusters of substantially spherical pellets connected to one another by a wire (6).

12. The manufacturing method according to claim 11, wherein the spherical cavities (14) of the matrix have a diameter smaller than or equal to 4 mm.

13. The manufacturing method according to claim 11, wherein the adjacent cavities between which notches (15) are formed are arranged at a distance from one another comprised between 0.5 mm and 10 mm.

14. The offensive charge according to claim 2, wherein the alloy of the pellets (5) comprises from 90% to 98% tin.

15. The offensive charge according to claim 2, wherein the alloy of the pellets (5) comprises from 2% to 10% antimony.

16. The offensive charge according to claim 3, wherein the alloy of the pellets (5) comprises from 2% to 10% antimony.

17. The manufacturing method according to claim 12, wherein the adjacent cavities between which notches (15) are formed are arranged at a distance from one another comprised between 0.5 mm and 10 mm.

Description

[0045] The present invention will be better understood, and details relative thereto will appear, using the description provided below of one of its alternative embodiments, relative to the appended figures, in which:

[0046] FIG. 1 is a sectional view of a cartridge with a grease wad according to the invention.

[0047] FIG. 2 is a sectional view of a cartridge with a skirt wad according to the invention.

[0048] FIG. 3 is a diagrammatic illustration of a machine for carrying out the projectile manufacturing method according to the invention.

[0049] FIG. 1 shows a cartridge for shooting with a firearm, comprising the cartridge case 1, the butt 21 of which here is placed at the bottom. In the cartridge case 1 is a propulsive charge 2 and an offensive charge 3, which are separated by a grease wad 4 and a sealing member 44. The propulsive charge 2, in the lower part of the cartridge (partially hidden by the butt), is traditionally powder.

[0050] Another cartridge according to the invention, shown in FIG. 2, is a cartridge with a skirt wad 4. The skirt forms a well 41 having a curved base and ending with a shock absorbing element 42.

[0051] These two structures are of a known type. They contain the offensive charge 3, i.e., multiple projectiles 10 (as opposed to a bullet, which is a single projectile). Each projectile 10 comprises at least two pellets 5 connected by a wire 6.

[0052] In a first example, the pellets 5 are beads with a diameter of 3.5 mm, formed by an alloy of tin (94.5%), antimony (5%) and copper (0.5%). The connecting wire 6 that joins them is made from brass (lead-free quality). It maintains the pellets 6 in pairs, separated by a fixed distance of 7.5 mm, which form the projectiles 10. An offensive charge may be formed by 50 of these projectiles 10.

[0053] In a second example, the pellets 5 are pellets with a diameter of 2.5 mm, formed by an alloy of tin (95%) and antimony (5%). The connecting wire 6 made from brass (with no lead) the pellets 6 three by three, separated by a fixed distance of 6 mm. It is possible to produce an offensive charge comprising around one hundred of these projectiles 10, or 300 pellets.

[0054] The projectiles can be manufactured as follows, in reference to FIG. 3. A machine is used comprising a furnace 100 provided with a reservoir 110 able to contain the selected alloy. The device also includes a horizontal plate (not shown) mounted on a central rotation axis able to receive and rotate a polymer matrix. The matrix assumes the form of two separable molds, an upper one (not shown) and a lower one 11. An array of branched channels 13 is arranged between the molds. The upper mold is provided with a central upper orifice that is placed overhanging a nozzle supplied by means designed to bring the molten alloy from the reservoir 110, and to deliver a quantity of alloy into the central upper orifice of the matrix.

[0055] The branched channels 13 extend along a radial orientation from the center 12 of the molds and each end with a spherical cavity 14, having a predefined diameter smaller than 4 mm. Notches 15 joining adjacent cavities 13 are formed in one of the molds. The adjacent cavities 14 between which notches 15 are formed are placed at the desired distance from one another, comprised between 0.5 mm and 10 mm.

[0056] Next, the following process is used. The reservoir 110 of the oven 100 is filled with the compounds forming the desired alloy and is heated to reach the melting temperature of the alloy (i.e., 290 C. for a 90%-5% tin-antimony alloy). The lower mold 11 is placed on the plate of the device. Brass wires 6 are installed such that they traverse several cavities 14, by inserting them in the notches 15 to keep them in place. The matrix is closed by the upper mold and the plate is set in rotation. A quantity of alloy is poured through the central orifice of the matrix. The rotation is continued for around twenty seconds. It is left to cool for several minutes before removing the upper mold, then recovering the clusters of pellets connected by a metal wire.

[0057] All that remains is to separate the clusters into projectiles 10 with the desired length (number of pellets 5) and to place them in a tub of a boxing machine.