EP0143720B1 - Munition for sporting guns - Google Patents

Abstract

1. Ammunition for a hunting weapon of the type comprising an under-gauged projectile which is stabilized by a fin (4, 15) and powered by powder contained inside a case, formed of a penetrating part (3 or 12) and a sabot (4 or 13), characterized in that the sabot (4 or 13) is formed of a material which is not subject to fragmentation after the ejection and consists either of a single piece or of two separable pieces.

Description

The present invention relates to ammunition for hunting weapons.

We know that hunting big game requires the use of bullet cartridges as opposed to lead cartridges used for small game. These known hunting ammunition are therefore of the type comprising a projectile actuated by a propulsion system.

The projectiles thus used are generally made of lead or steel, but their diameter is generally equal to the caliber of the weapon. It is noted that, by their relatively large mass, their low initial speed and their geometry, these projectiles are unstable on their trajectory, in particular when they are fired from a smooth tube, their significant aerodynamic braking leads to reducing and limiting their range of use, and decreases their effectiveness at medium range.

In addition, even in the case where the projectile has an ogival part, there is a tendency for longitudinal and lateral ricochets during very inclined or grazing impacts. Finally, the profiles of conventional bullets or projectiles can damage game meat by shredding it or crushing it in places, which is detrimental to the quality and preservation of this meat.

Documents FR-A-2 300 319 and FR-A-2 468 870 disclose hunting ammunition whose projectile, slightly under-calibrated, is guided along its trajectory by a plastic coating of which it remains integral. This plastic part extended towards the rear must play both the role of flock to ensure the tightness in the tube and the role of empennage to stabilize the projectile which, fired from a smooth tube, does not is not animated with rotation. This configuration only allows these two incompatible functions to be performed very poorly.

Document FR-A-2 335 818 describes a hunting ammunition according to the preamble of claim 1 and the projectile of which is constituted by a pointed "dart" totally surrounded by a shoe made of expanded polystyrene comprising at least three combined and separable parts. This shoe has parts made of fragmentable material which separate under the effect of the thrust gases. After ejection of the projectile from the tube, fragments are thus dispersed with very high speed, which constitutes a major drawback for the safety around the shooter.

The present invention provides a solution to the problem posed by security to the shooter, by seeking to reduce the number of components of the shoe to obtain a lesser dispersion of all or part of these elements when the projectile is ejected from the tube.

The present invention also remedies these various drawbacks by proposing a hunting ammunition comprising a lightened projectile with weak aerodymanic braking which has improved stability on trajectory even in transonic and subsonic conditions, greater efficiency, even at long distance, and which decreases notably the tendency to ricochets, without damaging the meat of the game too much.

To do this, the subject of the invention is an ammunition for a hunting weapon of the type comprising an under-calibrated projectile stabilized by empennage and actuated by powder contained in a case, constituted by a penetrator and a sabot, characterized in that the shoe is made of a non-fragmentable material after ejection, and either in one piece or in two separable parts.

In the military field, in particular that of artillery, large caliber ammunition arrows are known, fired from cannons with or without striped tube to act on armored targets, in particular battle tanks. These projectiles with high kinetic energy, since at very high speed and high density, and surface energy with very high impact since having a suitable tapered geometry, have the performance necessary for the perforation of modern armor. It has been discovered that the adaptation of these results in the very different field of hunting ammunition makes it possible to very significantly increase the probability of attacking game because of the short travel time on the very tense trajectory followed by the projectile. By using an arrow made of dense material, it is possible to reduce the dimensions to mass and thereby reduce the total weight of the ammunition. Above all, it can be significantly simplified and diversified, which reduces the cost.

The propellant system can be composed of propellant powder housed in a partially or fully combustible case.

The arrow consists of a tapered penetrator of dense alloy, for example based on tungsten or depleted uranium, or in conventional material for example of steel or lead, or of lead-antimony, provided with a tail unit for the stabilize on trajectory. The diameter of this arrow is much less than the diameter of the tube of the hunting weapon. This arrow is surrounded by a detachable launching shoe which ensures its speeding up, guiding and sealing during the passage through the tube of the hunting weapon. This shoe detaches from the indenter at the start of the trajectory. It can consist of one or more elements made of light materials; light alloy, plastic, composite materials, loaded cardboard etc.

• -la figure 1 représente schématiquement l'organisation de la munition selon l'invention,
• - les figures 2 à 5 illustrent diverses variantes de systèmes propulsifs adaptables à la munition selon l'invention,
• - les figures 6 à 9 montrent diverses configuration de sabots de lancement de pénètrateur combinées à titre indicatif avec le système propulsif illustré sur la figure 2,
• - la figure 10 montre une variante de la munition selon l'invention adaptée pour être tirée par un tube rayé.

Other advantages will appear in the description below of several embodiments of the hunting ammunition according to the invention, given without limitation with reference to the dessun on which:

• FIG. 1 schematically represents the organization of the munition according to the invention,
• FIGS. 2 to 5 illustrate various variants of propulsion systems adaptable to the munition according to the invention,
• FIGS. 6 to 9 show various configurations of penetrator launching shoes combined for information with the propulsion system illustrated in FIG. 2,
• - Figure 10 shows a variant of the ammunition according to the invention adapted to be fired by a striped tube.

FIG. 1 illustrates the general organization of a hunting ammunition with a conventional metallic or non-metallic casing 1, containing a charge of powder 2 constituting the propulsive system, of an penetrator 3 contained in a launching shoe 4, itself maintained in the cartridge. Conventionally, the powder is primed by a primer 5 struck mechanically into the bottom of the socket.

As regards the propulsive system, FIG. 2 shows a variant in which the powder 2 is housed in a combustible case 6 based on nitrocellulose closed by a shutter cap 7 which is not metallic combustible or not provided with a primer 5. The FIG. 3 shows the powder 2 housed in a fully combustible case 8, the bottom of which comprises a combustible primer 9. In FIG. 4, the propulsion system is constituted by a propellant block 10 with agglomerated charge without case directly in the combustion chamber, l rear seal being obtained using a shutter base 7 of the same type as that relating to FIG. 3 comprising a primer 5 with mechanical percussion. Finally, in the case of FIG. 5, the propulsion system is of the entirely combustible type, since the combustible primer 11 is integrated into the propulsion unit 10 itself. The powders that can be used are those from the field of conventional hunting powders. They are in principle simple base and different shapes (spherical, rods, tubular, multitubular, discs, flakes, rectangular, ...). Furthermore, a binder introduced into the propellant powder is essential to ensure the rigidity of the propellant block of the solutions relating to FIGS. 4 and 5, solutions which also require modification at the level of the breech system of the hunting weapon to perfect the tightness at the start of the blow.

FIGS. 6 to 9 show various types of arrow projectiles combined, by way of nonlimiting example, with a propellant system such as that shown diagrammatically in FIG. 1, comprising a conventional cartridge case filled with powder, closed by a base provided with a percussion primer. Any combination of various boom launch techniques and various propulsion systems is possible. These ammunitions are adapted to be fired from a hunting weapon provided either with a smooth tube, choked or not, or with a weakly scratched tube.

Figure 6 shows a penetrator 12, enclosed by a launch shoe 13 consisting of several elements held together by two belts 14a and 14b in contact with the chamber (23) of the tube of the hunting weapon. The very tapered penetrator 12 is terminated at the rear by a tail unit 15 for stabilization on the trajectory. The shoe consists of two longitudinally adjacent elements forming the tubular part 16 enclosing the central part of the indenter. These elements have external shoulders at the periphery of which are fixed the belts 14a and 14b which rest on the chamber of the barrel of the weapon. In addition to its functions of assembling the elements of the launching system, the belts 14a and 14b ensure on the one hand a good seal during the launching phase of the projectile and on the other hand allow to obtain a satisfactory ballistic regularity thanks to the pressure forcing developed during the creep of these belts to the forcing cone 26 of the tube of the hunting weapon connecting chamber 23 and core of the tube 27. Furthermore, they allow firing from choké tubes (case of hunting rifles). Materials such as lead, lead + antimony, plastics, composites, loaded or unloaded cardboard ... can be used for the production of these belts. The rear shoulder 17b constitutes a thrust plate subjected to the pressure of the propellant gases generated by the combustion of the powder, while the front shoulder 17a constitutes a guide plate.

It is noted that the shoe maintains the penetrator only in its central part, the tail unit 15 being located at the rear of the thrust plate, which makes it possible to qualify this launching system as a pusher tractor. According to the geometry of the elements, and in particular their longitudinal profiles, the elements of the sabot are detached from the indenter at the exit of the barrel of the weapon, either from the front towards the rear, or preferably from the rear towards the 'before to avoid the support of the elements of the shoe on the indenter during separation, or the shocks of these elements with the jibing of the indenter.

FIG. 7 illustrates another configuration of detachable approximately cylindrical shoe, presenting a thrust plate 18, and supporting the belts 14a and 14b, while it maintains the indenter at the rear of the tail unit. This system of launching is called pusher, its opening is generally done from the front. However, it is possible to make a shoe having a perforated front part 19 for the passage of the tail of the indenter, which then slides, as soon as it leaves the tube of the hunting weapon, inside the shoe and separates from it without that it does not open or fully opens.

In FIG. 8, we can see a detachable shoe which encloses the penetrator on its central part and has only one external projection 20 supporting the sealing belt 21. The pushing and guide plates are combined and placed in the middle of the shoe. The tail of the indenter is in direct contact with the propellant powder which also acts on the whole hoof which is then of the "saddle" type.

FIG. 9 illustrates an embodiment of the ammunition according to the invention comprising a tractor shoe. Indeed, the gases from the combustion of the powder act on the indenter at its tail 15, and thanks to the perforated part 22 of the shoe, on the front part 20 of the latter which supports the sealing belt 21 .

The projectiles shown diagrammatically in FIGS. 6 to 9 can either be entirely contained in the chamber 23 of the tube illustrated in FIG. 6 (while the length of this chamber is simply indicated in the other figures between the vertical mixed lines X and X ′), either partially or totally engaged in the barrel of the weapon, or partially engaged in the socket.

For use in a striped tube 24, FIG. 10 shows a hunting ammunition comprising a penetrator and, for example, a shoe of the type of that represented in FIG. 6, however having a sliding sealing belt 25 to prevent rotation of the projectile. The system is not essential if the weapon is slightly scratched.

The projectiles illustrated in FIGS. 6 to 9 and fired from smooth or slightly scratched tubes can receive a sealing wad placed at the rear of the launching shoe which ensures, in addition to a sealing function with propellant gases, a reduction the recoil shock received by the hunter. However, the pusher shoe of Figure 7 is best suited to receive a conventional commercial flock without modification of the latter. On the other hand, a wad would be detrimental to the proper functioning of the projectile in the case of shooting from a hunting weapon with a strongly striped tube as indicated for example in FIG. 10.

Depending on the type of weapon used, the caliber of the weapon, the nature of the penetrator and the launch system used, the penetrator can have very variable dimensions. As an example, the following table shows the importance of the projectile depending on the weapon, from 3 calibers.

These results can be compared to those stipulated in the following table with conventional bullets, the results of which have been collected in the literature.

The comparison of these two tables clearly confirms the advantages which the use of a kinetic energy munition of arrow type, advantages which increase with the caliber. It should be noted that the kinetic energy at the muzzle referred to the frontal section of the projectile in flight (arrow or bullet) is three times greater for weapons of caliber 6 mm, 6 times greater for weapons of caliber 10 mm , and 20 times greater for 12 gauge shotguns. The surface kinetic energy at impact is one of the most important factors in fatally arresting large game encountered.

Furthermore, the present invention has been applied to hunting ammunition for a 12-gauge smooth-tube weapon, taking into account the following constraints.

The length of the conventional cartridge must be respected so that the new ammunition can be fired in an automatic rifle. This assumption is very restrictive because it does not allow to use all the intrinsic possibilities of a munition arrow. It is also necessary to respect the firing pressure under normal conditions of use, and obtain a quality-price ratio much higher than conventional ammunition.

Compared to the classic ball, an initial speed increase of around 20% is obtained. The aerodynamic drag decreases, which gives the penetrator sufficient energy to destroy the big game at the usual shooting distances (in principle up to 200 m). At the mouth, the surface energy of the penetrator is 3 times greater and at 100 meters 20 times greater. In addition, the recoil impulse is reduced by 16%. The ammunition according to the invention has a high firing precision, therefore a high probability of reaching the usual firing distances.

Claims (4)

1. Ammunition for a hunting weapon of the type comprising an under-gauged projectile which is stabilized by a fin (4,15) and powered by powder contained inside a case, formed of a penetrating part (3 or 12) and a sabot (4 or 13), characterized in that the sabot (4 or 13) is formed of a material which is not subject to fragmentation after the ejection and consists either of a single piece or of two separable pieces.

2. Ammunition according to claim 1, characterized in that the sabot surrounds almost the whole of the penetrating part and has a front thrust plate and a perforated rear guiding plate.

3. Ammunition according to claim 1, characterized in that the sabot surrounds the penetrating part at the rear part thereof and has a rear thrust plate (17b).

4. Ammunition according to claim 1, characterized in that the case is partly or entirely combustible.

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