MXPA00001994A - Jacketed projectile with a hard core - Google Patents

Abstract

The invention relates to a jacketed projectile (100), comprising a tungsten carbide hard core (5) on the front side and an centered, interlocking soft core (8) placed on the hard core (5). A closed air space (6) is located between the front area (5a) of the hard core (5) and the tip of the projectile (4). This projectile configuration provides a very high penetration potential and good dynamic and ballistic properties, enabling the inventive projectiles to be used as munition for police snipers, especially to hit targets located behind a glass.

Description

ARMORED PROJECTILE WITH A HARD NUCLEUS DESCRIPTION OF THE INVENTION The present invention relates to a projectile according to the preamble of claim 1. The small caliber ammunition with hard core is used in particular by the precision shooters and aims at a precise penetration of the armored targets. The armored targets in the sense of the object of the invention are the protection vests (for people), the armored glass, the steel plates and the light metal shields. Ammunition of this type is known in various versions. These can be classified into those with a steel core type, those with a steel core type from a compact sintered material, and those with a medium to add to the hard core such as lead, aluminum and / or air. This ammunition has in common a steel casing configured most of the time as a solid projectile casing, plated steel casing or tombaga casing, which houses the cores and the media and includes them at least hermetically proof liquids.

In EP-A1-0 499 832 there is shown an armored projectile with a lead core, with a truncated cone shape on the rear face and a steel casing or a tombaga alloy surrounding it. The casing is also plated with a thin layer of tin, for the reduction of deposits in the barrel of short firearms. From GB-A-592 538 a small caliber projectile is known, in which the hard core is housed unsupported in the projectile shell, between its front area and a mass of light material on the back side. In this way the desired weight distribution is achieved, the manufacturing tolerances are compensated and the friction in the rifle barrel is reduced. GB-A-601 686 shows another armored projectile with a configuration of a hard core and a soft core which is especially favorable from the point of view of the manufacturing technique. The hard core has on the front side for this purpose a diameter that is partially smaller than the inside of the shell projectile; The hard core is also supported by a soft body made of light metal, with an axial 1 ong it ud, which has a notch on the front face that serves to center the hard core and becomes a wide hollow space and in the form of a spherical cap. In this way, slits and notches are formed between the cores and the projectile shell, which allows displacements of material in the compression and sealing of the projectile and gives rise to a compressibility, by which manufacturing tolerances can be compensated. The known projectiles present a probability of first impact in the target that is only insufficient, due to its shape and its internal and external ballistic characteristics, and show an insufficient penetration capacity in the case of the armored targets. Document WO 89/03015 discloses a projectile for a large caliber firearm, especially for an artillery piece, where the projectile has a form-fitting connection between the projectile shell and its core, for the increase of the power of drilling and to prevent a detachment of the projectile shell. Additionally, geometrical core shapes and special rear configurations are indicated, as well as throttles in the central part and in the rear part of the projectile.

A hollow chamber, provided between a sharp-angled frontal area in the core and the interior of the projectile shell in a variant of that invention, is filled with lubricating grease, plastic material or gunpowder to preserve the shape of the tip of the shell. projectile on the white; this also reduces the friction that results during assembly. The proposed measures and means they can only be applied in a very limited way to a small-caliber ammunition and make it considerably more expensive. A small-caliber ammunition and its manufacturing process are known from EP-A2-0 106 411. The projectiles manufactured and optimized in a relevant way serve mainly as combat ammunition for infantry and already have good ballistic characteristics. But this ammunition does not possess the high final ballistic energy required by precision shooters, which is necessary for the penetration of shields. Hence, it is the object of the present invention to create a small-caliber ammunition which does not present the drawbacks of the current l of technology and especially has a high penetration power in the case of armored targets, low sensitivity to side wind and also an increased precision. The ammunition that has to be created must make it possible for the precision shooters to accurately beat the targets that are behind a glass, in case of a police action. This objective is achi by combining the features of claim 1 through claims 9 and 10. It has been found that the support of the hard core with form drag on the internal geometric contour also in the form of a warhead of the envelope of projectile results in an extraordinarily compact body, with symmetry of revolution and exact measurements, with very good penetration, ballistic and dynamic characteristics. The frontal area of the hard core which is smaller in comparison with the internal geometrical contour guarantees its flush contact with the outer geometric contour and includes with it an air chamber that reinforces the easy detachment of the projectile envelope and the hard core in the penetration to a shield of the target, so that to 34%, preferably 31% for the soft core mass, and preferably 25% of the total mass for the projectile shell. This results in a weight distribution in the projectile that is ideal in the case of small caliber ammunition, 5 that is, the center of gravity is optimal for the ballistic trajectory of a projectile. By placing a thin brass disk in front of the edges of the shell, in the back of the projectile, is an influence on the cores that make them gas-tight, so that the emission of heavy metals by the shot is eliminated. By means of an angle of conicity between 14 ° and 18 °, preferably 16.5 °, an optimal centering of the soft core on the hard core and with symmetry of revolution is achieved. The smaller taper angles, below 14 °, also give rise to a centering adequate. A surface treatment of the hard core by means of a wet abrasion for several hours, that is, in practice a treatment of up to twelve hours in the bath of water at room temperature, in which the cores are polished mutually until they are smooth and bright, it is optimal from the economic point of view. Obviously, other methods that also cause the desired surface fineness and, therefore, the capacity to drag the shape of the envelope are considered. By means of a manual engagement of the cores in the envelope, manufacturing tolerances can be controlled and determined in a functional manner, so that material tensions and / or deformations do not occur, which could inconveniently influence the symmetry of projectile revolution. With the help of two practical examples of embodiment, the object of the invention is illustrated in more detail below. They show: FIG. 1 a preferred projectile with the nuclei provided with symmetry of revolution, which is introduced in a pod with propellant charge powder, the figure an increased representation of the hard core of FIG. 1 in its characteristic size proportions , FIG. 2 shows a variant of the projectile of FIG. 25 1, with a bulged hard core tip and a modified rear zone, ^ llgg | 3 shows impact diagrams of a 7.5 mm caliber hard core ammunition, resulting in a shooting distance of 200 m, FIG. 4 the projectile velocity of the ammunition according to FIG. 1 or FIG. , depending on the distance and considered in comparison with the current level of the technique, figure 5 the decrease in ammunition speed according to figure 1 or figure 2, at a shooting distance of 100 to 800 m and compared to the current level of the technique, figure 6 the sensitivity of the projectiles against the side wind, in comparison with two projectiles produced according to the current level of the technique, figure 7 the projectile impulse of the ammunition according to figure 1 or Figure 2, indicated along a trajectory distance of 800 m and compared to the current level of technique, shows the projectile energy of the ammunition according to Figure 1 or Figure 2, ind. Along the path distance of 800 m and compared to the current level of technology, the figure shows the momentum of the hard core of the ammunition according to Figure 1 or Figure 2, displayed along a trajectory distance. of 800 m and compared to the current level of the technique, figure 10 the hard core energy of the ammunition according to figure 1 or figure 2, indicated along a path distance of 800 m and compared to the level current technique, figure 11 the discharge power of three different calibers of hard core ammunition, depending on the firing distance for a first type of armored glass and in comparison with the standardized specification, and figure 12 the power of discharge of the three different calibers, depending on the shooting distance for other types of armored glasses and in comparison with the standardized specification.

In FIG. 1, a cartridge case known per se is designated by reference 1, which contains a powder charge 2, also known per se, as a high-power propulsive charge. In the cartridge case 1, a projectile 100 is inserted, the tip 4 of which is formed by a steel casing 3. It has a form of warhead 7a on its front side, which becomes a cylindrical central piece 7b and which presents a torsion groove 12 for fastening the sleeve 1 and ending in a rear area 9. At the closed end 10 of the cartridge sleeve 1, a primer primer 11 is introduced in the conventional manner known. The hard core 5 has a rear area 5b which has the shape of a truncated cone, which is occupied by an interior contour of a perfectly adapted soft core 8. A front area 5a is configured as a truncated cone with an angle of conical ß and between this and the concave inner profile of the projectile tip 4 is an air chamber 6 of great functional importance. The steel casing 3 encloses with force the three components included: the soft core 8, the hard core 5 and the air 6, by means of a flange 13 on the rear side. .... ^^ i ^^ - fft | ^^^^, ^^^^ 3L The pieces that have the same function are endowed with the same sign of reference in the following figures. The representation of the hard core 5 in the Figure 5, enlarged in relation to Figure 1, contains the measurement data that are valid for a 7.5 gauge in a preferred embodiment: total length Li of the hard core 5 = 19 mm front length L2 = 15 mm 10 diameter D of the cylindrical central part = 6.64 mm radius of warhead R = 61.6 mm rounding r = 0.2 - 0.02 mm angle of taper a = 16.5 ° 15 diameter d of the end of the truncated cone = 4.28 mm acute angle ß = 80 ° A second variant of a 100 'projectile with a steel casing is represented in figure 2, where in this case only the modifications are commented on in relation to figure 1. central area 5a is configured as a spherical cap and also serves, as in figure 1, for the compensation of manufacturing tolerances and also forms the gas-tight air chamber 6 25 in the projectile tip 4, through of the core-shaped piece of warhead ^ Gg ^ jg ^ gg ^^ jg¡gl hard 5 ', which is adjacent flush and contiguous with the projectile envelope 3. The rear zone 5b of the hard core 5 'has an axial type turning having a small conicity, not visible, and on which the soft core 8 is centered. A brass sealing disk 14 is inserted into the projectile 100' by the back face, which gas-tightly seals the steel casing 3 by means of a flange 13, that is to say, prevents the gases and / or vapors of heavy metals from being released with the shot. The soft core is shortened in the thickness of the disk 14, to maintain the same projectile length. The hard core is composed of tungsten carbide with cobalt alloy WC / Co 88/12 in both variants, with a mass of 5.6 g and a hardness according to Vickers HV of 1300 kp / mm2 and a mechanical resistance to the torsion of 3000 N / mm2. The soft core is composed of an alloy of lead and tin Pb / Sn 60/40 with a mass of 3.9 g. The steel casing 3 weighs 3.11 g. Therefore, the total mass of the projectile reaches 12.61 g in the first version, that is, without the hermetic disk 14.

»Ffltó ^ 4 *« * In numerous firing tests, the object of the invention was investigated, over a distance measured at 800 m and compared to the current level of the technique. Figures 3a to 3c show characteristic diagrams of impact on the target at a shooting distance of 200 m, where in each case 20 shots were made in a series, on a white disk with an inner circle of 5 cm and a outer circle of 10 cm in diameter. The share of impacts in the innermost area of the disk (in the so-called "targets") reached 95%. The ammunition used corresponds to the Swiss ordinance caliber (7.5 x 55). The same test has not been represented with ammunition according to the current level of technique (caliber .308); the impact quota on the target that was achieved in this case reached less than 65%. The speed of the projectile 100 according to the invention is represented in figure 4 in relation to the current level of technique, designated with reference 0.308. At the same time it can be seen that the speed of the projectile 100 from the beginning (initial speed V0) of 850 m / sg decreases practically linearly to only 580 m / sg for a distance of 800 m. The representation in figure 5 of the decrease in speed in m / sg per meter, in 5 function of the shooting distance in meters, underlines the information in figure 4. In this case, the high proportionality draws attention in turn. linear from a shooting distance of 200 m. Figure 6 shows the lateral deviation of three projectiles in case of a wind with a speed of 4.8 m / sg and that is present at right angles in relation to the firing trajectory. The projectile 100 according to the invention shows appreciably better values compared to the values 308 corresponding to the current level of technique; For comparison purposes, an old GS 11 ordinance ammunition was also investigated and in Figure 6 its 20 relatively good values are presented. In addition, the projectile impulse was investigated in mkg / sg, as a function of the firing distance, and are shown in figure 7. The projectile 100 also shows in this case considerably better values than those of the projectile .308.

The projectile energy in J (joules) indicated in figure 8 for the projectile 100 are considerably higher compared to the projectile .308, according to what was expected. This shows that even at a shooting distance of 800 mm, the projectile 100 still has a very considerable energy of approximately 1800 J and, therefore, still has a high penetration capacity. In order to offer complete information, the impulses of the hard core in the projectile 100 and the energy of the projectile 100 in relation to the current level of the technique were measured and indicated in figure 9 and figure 10. The surprisingly good firing results of the object of the invention must be attributed, not ultimately, to the favorable weight distribution within the projectile. The tests of penetration in the shields defined at the beginning completely confirm the measurement results in practice. It has been proved that projectile casings made from CuZn5 or CuZnlO brass alloys show results equivalents, as shown in figures 11 and 12, regarding penetration tests carried out with shielded glass of class C4 or C5 (inhibition of penetration according to DIN 52290/2). In Figures 11 and 12 is shown striped and 5 is designated with the reference "i" the area of the target, ie, the armored glass transferred safely, while the area above is valid as not transferred and for this is designated 0. 0. According to FIG. 11, the test requirements as reference R for the so-called insulation glasses of class C4 are registered in the lowest column designated with the RC reference. According to DIN 52290/2, you can not take place no penetration at a distance of 10 meters with a solid casing ammunition, lead core and a caliber 7.62 x 51 mm type FMJ, in case of three hits on the target under the test conditions. This means in this case that the zone O not scratched, consequently: surely it has not been traversed. An ammunition of caliber 7.62 x 51 mm (type AP) configured according to the invention crosses the same glass already with a single shot even from a distance of 60 m. The caliber 7.62 x 51 mm (type AP) crosses even from a distance of 110 m and buffet »Ag-? 'fZJ Wii? e 11 the caliber of the type .300 rínMag (type AP) penetrates through this type of glass even from a distance of 150 m. The zone 0 not scratched means in this case: also crossed with a certain dispersion possibly in the limit zone, which is justified by the residual kinetic energy that exists even after the penetration of the glass and that can be checked in all cases . Figure 12 is structured analogously; in this case it was fired on a glass of class C5. The reference RC5 designates the standard test requirement for glass of class C5; again for a 7.62 x 51 mm caliber ammunition (type FP / AP), that is, in this case a solid projectile shell with a steel core. The ammunition according to the invention is again, several times more powerful in the penetration. The corresponding ammunition of caliber 7.62 x 51 mm (type AP) also gives rise to penetration for a distance of 60 m to the target in the case of this kind of glass; caliber 7.5 x 55 mm (AP type) at a distance of 110 m and caliber 7.62 x 51 mm (AP type) at a distance of 150 m. But in all three cases only a low residual energy can be detected after penetration through the glass.

In addition, no significant deviation of the projectile was detected in any of the cases of the glasses that have to be traversed in an imaginable police action. In the case of a projectile that does not strike perpendicular, deviations of less than 5o were determined, for angles of incidence of up to 30 ° with respect to the perpendicular. Obviously, the use of The projectile construction according to the invention is not limited to the calibers mentioned above; the projectiles can also be adapted to the other small-caliber ammunition, in particular .300 Winchester Magnum, with the relevant charges larger propellers and also known per se. ^ jtj £ iSSjíiájjtiÉ ^? i ^^^

Claims (10)

1. Small caliber projectile with a steel, plated steel or brass casing, with at least one hard core disposed on the front side in each case, with a density of more than 10 g / cm3, and at least one soft core in the form of truncated cone, arranged on the back side and with a density of less than 10 g / cm3, while the The exterior geometrical outline of the projectile shell considered from the projectile tip is configured with the shape of a warhead, becomes a cylindrical central piece and ends in a conical rear area, while the piece of the The hard core, also in the form of a warhead, rests with its smooth surface on the internal geometrical contour of the casing with a shape-shaped drag along a wide area and forms a hollow space between the projectile casing and the frontal zone of the core. 20 hard, characterized in that the hard core becomes a truncated cone shape or a spherical cap shape in its front area and has a polished surface, because there is a closed air chamber between the inner surface of the 25 shell projectile and the front area of the hard core, because the rear area of the hard core is MI'ailMltb '** "~ * ^" < fttfi, M, aJ ^ configured in the form of cone cone, because the soft core is supported centered with shape drag on the truncated cone of the hard core and where it fills the cylindrical part in its entirety 5 and the rear area of the projectile envelope that is configured with a geometric frustum contour.

2. Armored projectile according to claim 1, characterized in that the casing is plated with an alloy of copper and zinc on the outside.

3. Armored projectile according to claim 1, characterized in that the hard core is tungsten carbide alloyed with cobalt and has a density of more than 14.0 g / cm34.

Shielded projectile according to claim 1, characterized in that the soft core is composed of lead and / or tin and has a density of less than 7.3 g / cm3.

5. Armored projectile according to 25 claim 3 and claim 4, characterized in that the hard core matters between 42% and 50% and the bladed core imports between 28% and 34% of the total mass of the projectile.

6. Armored projectile according to claim 1, characterized in that the soft core is gas-tight sealed on the back side, by means of a brass disk which seals the projectile envelope with force.

7. Armored projectile according to claim 3 and claim 4, characterized in that the hard core presents' a truncated cone on its back side, with an angle of taper between 14 ° and 18 °, and because the soft core is placed with its cone internal on the truncated cone with shape and the same conicity angle.

8. Armored projectile according to claim 3 and claim 4, characterized in that the hard core has a truncated cone on its back side with an angle of taper between 0.5 ° and 14 °, and because the soft core with its inner cone is placed on the conical truncated cone with the same conicity angle.

9. Process for the manufacture of a shielded projectile according to claim 3, characterized in that the hard core is subjected to an abrasion in water after its compression and sintering molding, until it is bright.

10. Method for manufacturing an armored projectile according to claim 1, characterized in that the tolerances of the individual components are chosen so that the hard core can be inserted by hand into the interior space of the envelope and the soft core can also be placed hand by sliding on the rear part of the hard core, before the beading of the rear part of the projectile is carried out.