KR20070007924A - Lead-free projectile - Google Patents

Abstract

Disclosed is a small-bore projectile (100) comprising an outer jacket (5) made of tombac, a hard core (4) made of hardened steel, and a hollow jacket core (8) that is also made of tombac. The kinetic energy is substantially transmitted to the hard core (4) when a target (Z) is hit such that said hard core (4) penetrates the target (Z). The ductile jacket (5) is supported by the jacket core (8) that is located on the inside and mushrooms up into a deformed jacket (5') without fragmenting. The inventive projectile (100) is provided with a good flying behavior and a great final ballistic performance and can be produced in an entirely lead-free manner. ® KIPO & WIPO 2007

Description

Lead-Free Projectile {Lead-free Projectile}

The present invention relates to a small-bore jacketed projectile that is free of lead.

Such bullets are known in a variety of designs. It can be divided into hard cores made of steel, those with hard cores made of dense sintered material, and those with medium added to hard cores such as lead, aluminum and / or air. have. Such ammunition which is commercially available is usually accompanied by a full jacket, ie a steel jacket which is a jacket made of a plated steel jacket or a copper / zinc alloy (tombac jacket). In this connection, the jacket receives one or more cores and intermediates and encloses the cores and intermediates in a manner that is at least full of liquid.

Small inorganic bullets and their manufacturing processes are known from EP-A2-0 106 411. Correspondingly, projectiles optimized are mainly used for infantry ammunition and already have good aerodynamic properties. However, these bullets do not have the high final ballistic energy needed to penetrate the armor surface needed by the shooter. A further disadvantage is the significant amount of hard lead in the core (98% lead + 2% zinc), which is toxic to the environment in both empty and ammunition and is therefore undesirable in these days and even banned in some countries.

Jacketed projectiles with penetration performance and target accuracy (WO 99/10703) are solid cores made of tungsten carbide that are held in an interference-free manner that fits through the brass disk in the jacket in a non-gas-free way, and as an additional intermediate, lead (copper) / Zinc 60/40) with a soft core. Thus the outflow of heavy metals and / or vapors when foaming is hindered; Toxic effects still remain in the target area. In addition, the manufacture of such projectiles is expensive for mass use (infantry bullets).

Another jacket projectile of the 9mm caliber pistol is sold under the name SWISS P SELF 9mm Luger (RUAG Ammotec, Thun / Switzerland, originally RUAG Ammunition Thun / Switzerland). In this case, the projectile consists of two sleeves that are pushed into each other, with the inner sleeve sealed at the rear and opening upwards and the outer sleeve sealing the large air. However, these projectiles are only designed for soft targets, in which case they can penetrate smoothly; It can be made free of lead.

Therefore, it is an object of the present invention to provide a small diameter projectile (smaller diameter = smaller than 0.5 ") suitable for a solid target, which can be manufactured economically, has high penetration performance and target accuracy, and is suitable for launch or target area. It does not emit heavy metals in. The projectiles provided do not contain lead in the core in particular.

The projectile according to claim 1 can be easily produced and in hard targets (thin plates) etc., delivers almost all of the kinetic energy to the hard core penetrating the target. In this regard, the mass is preserved 100%; In the bullet holes, mushroom-shaped collars are formed by a tomback jacket corresponding to the original weight of the jacket.

Thus it is demonstrated that no heavy metal and / or metal vapor is released.

The same can be found as subject of the invention according to claim 2. This shows a high final ballistic performance and, despite the presence of a solid core on the entire cross section surface, cracks were found in the target in actual tests.

Advantageous developments of the subject matter of the invention are disclosed in the dependent claims.

Projectiles and air spaces having a peak-shaped outer shape according to claim 3 are particularly advantageous for ballistics. It is shown that the required pressing-in of the rigid core can be performed accurately and with relatively low forces. In addition, after a short travel path, the pulse transmission of the core allows the penetration of the jacket to result in lower energy losses.

The embodiment according to claim 4 has a great advantage in that the central pulse transfer is made from the jacket core to the rigid core.

Quite broadly, in claim 5, the flight operation of the projectile is provided by the center of gravity position. The center of gravity can be optimized by dry design and by dimensioning the rigid core and in particular the hollow space (bore) in the jacket core.

In claim 6, the alloy tool steels can be fitted to a rigid core, processed and surface treated in a conventional manner.

The same materials for the outer jacket and jacket core according to claim 7 prove to be very economical and are also advantageous for density, assembly and thermal expansion.

The restriction according to claim 8 improves the connection to the cartridge sleeve and allows it to be simply assembled.

The thickening of the jacket in the front region described in claim 9 reduces the ricochet during sharp angled shots to rigid targets and also contributes to determining the center of gravity.

Embodiments of the projectile appear to be particularly suitable for the bore and projectile form cited in FIG. 10.

The current need for lead-free projectiles is evident in the choice of material manifested in the claims; See claim 11. As the position of the center of gravity is optimally adjusted by the dimensioning of the individual components and the hollow space, a standard filling material made of heavy metal in conventional projectiles can also be dispensed.

The invention is explained below with reference to the embodiments and figures.

1 is a projectile according to the invention fitted with a known cartridge sleeve;

2 is a cross-sectional view of a preferred embodiment of the projectile of FIG. 1;

3 is a cross-sectional view of another solution of a lead-free projectile;

4A is a view of a conventional projectile (according to prior art) when hitting a target;

4b is a view of the projectile according to FIG. 2 when hitting a target; And

4c is a view of the projectile according to FIG. 3 when hitting a target.

The tip of the projectile 100 is indicated by 1 in FIG. 1. The flange 21 is inserted into the reduced diameter of the peripheral crimp 6, which is a component of the known cartridge 20. Standard explosives 24, which serve as propellants of the projectile 100, are located within the cartridge 20. An impact fuse 23 (SINTOX, trademark of RUAG Ammotec GmbH, Furth, DE) is inserted into the base 22 of the cartridge 20.

A preferred rotationally symmetrical projectile 100 is shown in FIG. 2 in an enlarged view.

The actual end 1 does not exist; In reality it is the tip which is the shape of the spherical cup 2. As a result of the different radii, a small air space 3 formed between the rigid core 4 and the outer jacket 5 is located inside the projectile 100. In the formation of a blind hole, the jacket core 8 having the central hollow space 10 is attached to the rigid core 4 while forming a fit. The center of gravity 7 of the projectile is located above the hollow space. An outer periphery annular groove 6 described herein and represented by a diameter in FIG. 1 is located thereon.

At the rear, the end of the jacket 5 is conical tapered and ends at the layered portion at an angle α of 30 °, which layered portion is joined with the end flange 9 and the two cores ( Hold 4 and 8 together for interference fit.

The bore, the diameter of the projectile 100 denoted by K, is 5.56 mm in the current case and is of the form SS 109. The diameter 6 of the crimp section is 5.45 mm. The solid core 4 weighs 4 g and is made of hardened tool steel (material according to DIN 1.5511) and converted to phosphate after carbon mixing (infiltration depth = 0.3-0.5 mm). Surface hardness is 570 HV1.

In this embodiment, the rigid core 4 has a lower conical end of 90 ° which is located in the corresponding receptacle on top of the jacket core 8. This shape can change at will; However, a shape similar to centering in the center is advantageous, which facilitates the insertion or pressurization of the core and ensures rotational symmetry of the projectile.

A rigid core 4 made of earth bag is also advantageous; Surprisingly, this produces similar final ballistic performance.

Projectiles can be manufactured by standard production equipment and generally by deep drawing and pressing.

The rigid core may also be made of other materials, for example a sintered material such as tungsten carbide. Other projectile jackets are also conceivable for the tombback. The jacket core may also be composed of other materials having a similar or greater density. However, in all alloys, outflow of heavy metals at launch and target locations is considered.

In figure 3 a variant of the projectile is shown, in which the same working part is shown with the same reference numeral.

In contrast to the subject matter according to FIG. 2, in this case, there is no rigid core. A single jacket core 8 'similarly fills the space of the rigid core 4 of FIG. The combined hollow space 10 ′ is shorter than the hollow space 10 and has a smaller diameter. In conclusion, the mass of the entire projectile 100 'is increased so that approximately the same final ballistic performance and effect are obtained at the target.

On the front side, the end space 10 'is tapered and almost closed, so that a dense end is produced when hitting the target with the front part of the outer jacket 5.

In both variants, after measuring the results, theoretical observations and comparisons with other (preceding) launchers show exceptionally good results.

The hollow spaces 10 and / or 10 'allow for transverse contraction in the total barrel (rifle), which reduces wear (polishing) for solid projectiles, especially in the rifle groove. At the same time, the firing speed v _o of the projectile 100 and / or 100 'in the muzzle is larger than the projectile without the hollow space 10 and / or 10'.

After a 570 m flight distance (NATO target), the low drag coefficient c _d of the projectile (SS109 type) according to the invention still reaches an impact speed of 470 m / s; The steel sheet used is Stanag 4172, 3.5 mm thick with 55-70 HRB hardness (400 N / mm ² ) and is punched smoothly.

Accurate spin stabilization actually affects flight path stability and reproducibility, even in side winds. As a result of the choice of material and high firing rate, the kinetic energy is larger than the comparative projectiles as in the tests already shown. The accuracy of standard weapons can be increased with the subject of the present invention. Thus, for example, all of the bullets fired at 25m target distance (repetitive firing) are located in a dispersion circle of diameter less than 50mm. At a firing distance of 300 m, a standard deviation S _D <35 mm can be found. In practice, this means that only two projectiles of fired bullets located on a circular surface with a diameter of 110 mm are approximately 80 mm offset from the center (target).

As the launch test for soap shows, in contrast to many other projectiles according to the prior art, the demands of the International Committee of the Red Cross (ICRC) have also been fully fulfilled with respect to wound ballistics.

4A shows a conventional rigid core projectile 200 before or during impact on target Z (steel). The steel jacket 50 explodes at the target Z, the hard core 40 made of tungsten or steel penetrates into the target Z due to the high kinetic energy, and the lead core 30 following it impacts. It is partly liquefied in time and even vaporized by sublimation. This can be seen by the evaporation cloud 30 'and after its condensation it can also be seen that traces of lead remain on the target.

The combination of elastic and plastic impact with high deformability occurs in the projectile 200 (the fracture of the material in all respects). The material of the projectile 200 which is fragmented and still detected at the target Z no longer coincides with the initial weight at the muzzle.

In contrast, in one projectile 100 of FIG. 4B, the same mass can also be detected in the target water Z. FIG. In this regard, the hard core 4 (steel or tomback) also penetrates into the target Z. The outer jacket 5 is mushroomed into the deformed jacket 5 'at the target Z and passes almost 100% of kinetic energy through its soft jacket core 8 to the rigid core 4; On either the jacket 5 or the jacket core 8 there is no crushing of the material. The pulse direction is preserved.

FIG. 4C shows a similar view: Compared to FIG. 4B, the modified projectile 100 ′ penetrates with the crushed and flattened end 1 ′ at the target Z. FIG. The pulse direction is also preserved, the jacket core 8 'impacts into the air space 3 and compresses and barks the air space marked 8 ".

Included in this specification.

Reference Number List

1 end (virtual) 1 'flattened, crushed end

2 spherical cups 3 air spaces (hollow space)

4 Hard core (hardened steel; tomback) 5 Outer jacket (tomback)

5 'Deformed Jacket (5) 6 Crimp / Diameter

7 center of gravity 8 jacket core

8 'Jacketed Core 8 "Barked Jacket Core (8')

Hollow space of flange 10 8 located at 9 5

10 '8' hollow space 20 cartridge sleeve

Base of flange 22 20 at 21 20

23 Impact Fuse 24 Explosives / Propellants

30 lead core 30 'leaded steam cloud

40 hard core (tungsten; steel) 50 steel jacket

100, 100 'projectile 200 conventional solid core bullet (projectile)

K bore Z target (steel plate)

α angle (donation angle)

Claims (11)

An outer jacket 5 made of a copper / zinc alloy enclosing a substantially cylindrical hollow space; A rigid core 4 made of steel or sintered material inserted into the hollow space towards the end; A jacket core 8 made of a copper / zinc alloy attached in a fit shape to the rigid core 4; A hollow space 10 of the jacket core 8 which is centrally located and one side is open; An open face of the hollow space (10) lying against the rigid core (4) and sealing said rigid core; And Small-diameter projectiles having a peak arch or conical front region, a cylindrical central portion and a conical extending tail region, including a tail portion of the jacket core 8 holding at least a trailing region of the jacket 5 in an interference fit at the periphery 100. An outer jacket 5 made of a copper / zinc alloy that encloses a substantially cylindrical hollow space; A hollow space of the jacket 5 including only the jacket core 8 'with the hollow space 10' and the air space 3; A hollow space 10 ′ comprising a gap in which the inner edges are tapered on the front surface at least partially in contact with each other; A small diameter having a peak or conical front region comprising a tail portion of the jacket core 8 'holding the trailing region of the jacket 5 with at least a peripheral fit, a cylindrical center portion and a trailing region extending conically Projectile 100. The method of claim 1, The cylindrical hollow space in the front inner region is defined by the shape of a spherical cup, The rigid core 4 also has a round cup shape at the end, The radius of the round cup of the hollow space is greater than the radius of the end of the rigid core so that the tip is at least approximately spherical cup-shaped, with the air space 3 at the end in the hollow space in the jacket. Small caliber projectile with a front area of the shape. The method of claim 3, wherein The trailing region of the rigid core 4 is conical, The conical end projects a small diameter projecting projecting into the hollow space (10) of the jacket (8). The method according to any one of claims 1 to 4, The small diameter projectile of the projectile is located in the longitudinal axis and in the area of the hollow space (10) of the jacket core (8). The method according to any one of claims 1 to 3, The hard core (4) is a small diameter projectile made of a high density sintered material such as alloy steel or tungsten carbide. The method according to claim 1 or 2, Small diameter projectile, wherein the outer jacket (5) and jacket core (8) are made of the same copper / zinc alloy. The method according to any one of claims 1, 2 and 5, The outer jacket (5) comprises a circumferential, peripheral squeeze flange with the front end of the cartridge sleeve (20) flanged. The method of claim 3, wherein A small diameter projectile wherein the material of the jacket (5) in the front region is thickened by at least a factor of two compared to the cylindrical region and the rear portion. The method according to any one of claims 1 to 9, The projectile has a 5.56 mm (0.223 "or 0.224") bore. The method according to any one of claims 1 to 10, The projectile is a small-diameter projectile is not lead.

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