FI20236009A1 - Projectile, seal ring for a projectile, and method for sealing a projectile - Google Patents

Abstract

The invention relates to a sealing ring (3) for a projectile (1) which seals the gap between the projectile (1) and the barrel of a weapon when the weapon is fired, whereby the sealing ring (3) comprises a part of the sealing ring (3) located inside the groove (2) of the projectile and a part of the sealing ring (3) extending outside the groove (2). The sealing ring (3) further comprises a space/cavity (6) extending around the entire projectile (1), whereby a slit (7) or several channels (8) open into the space/cavity (6), through which the gunpowder pressure generated during firing enters the space/cavity (6) and the mouths of the channels (8) or the mouth of the slit (7) are positioned in the outer part of the groove (2) of the sealing ring (3) such that said mouths are located in the part of the sealing ring (3) facing the rear of the projectile (1). The invention also relates to a projectile (1) comprising a sealing ring (3) and a method for sealing the projectile (1).

Description

PROJECTILES, PROJECTILES SEAL RING AND METHOD OF PROJECTILES

FOR SEALING

The invention relates to a projectile, a projectile sealing ring and a method for sealing a projectile according to the independent patent claims. The solutions according to the invention are suitable for use in particular, but not exclusively, in heavy weapons, where they offer improved accuracy and impact velocity compared to traditional projectiles.

Cartridges suitable for weapons typically consist of a projectile, which is a general term that includes all projectiles that can be fired. The main types of ammunition are bullets, grenades and special ammunition. Ammunition can include, among others, sharp arrows, blunt-headed flintlocks, slingstones, cannonballs, shrapnel and stones fired from catapults. A cartridge, on the other hand, refers to an ammunition combination in which the projectile, with any fuzes, the case, the powder charge and the primer are combined into one whole.

A cartridge contains all the elements needed to propel a projectile as a single unit. Almost all small-caliber firearms are cartridge-fired weapons.

In cartridge firing, the projectile and the propellant are loaded into the weapon separately. This type of firing is used especially in large-caliber (over 100 mm) cannons, where the use of cartridge firing does not make sense for technical reasons: the physical size and weight of the cartridge would increase too much. In this case, the projectile is loaded into the chamber first, and then the cartridge containing the propellant, which can be in a brass case containing a fuze, or in a textile or cardboard package, in which case the separate fuze is inserted last before closing the breech.

N Textile-wrapped powder pouches are popular, especially for very large-caliber naval guns,

S 25 — so the amount of propellant can be easily adjusted in relation to the shooting distance. 3

E Bullet usually refers to the non-explosive 2 projectile, or part of a cartridge, of a small-caliber weapon, usually less than 20 mm, that is fired at a target. Hunting gun bullets usually consist of a 3 brass alloy jacket and a lead core. The jacket can also be soft

S 30 — steel and a core of some other metal than lead. Bullets can also be made entirely of lead or another metal. Today, all-copper bullets are also used in big game hunting due to the material's suitable softness (does not damage the gun barrel) and toughness (changes shape on impact but does not fragment).

In everyday language, a rifling (groove, scratch) most commonly refers to a gently curving groove running along the inner surface of a firearm barrel, a rifling groove, the function of which is to cause a bullet or other projectile to rotate around its longitudinal axis during its flight to improve accuracy. Rifled barrels are now used in almost all rifles, pistols and cannons. Unrifled or smooth barrels are now used in shotguns, grenade launchers, rocket launchers, tank guns and some cannons.

The number of riflings in the barrel of a handgun is usually four to eight, but other solutions are also used. The number of riflings in rifle caliber weapons is usually four to six, and they are made for the entire length of the barrel. An exception is a separate, fluted reduction sleeve made for a shotgun. The distance during which one rifling makes a full turn in the barrel is called the rifling pitch. The depth of the rifling in a handgun is usually between 0.1-0.3 mm and — pitch about one revolution over a distance of 20-30 cm. A long bullet usually needs a short rifling pitch to stabilize. Too frequent rifling pitch can cause a phenomenon called overstabilization, in which the bullet does not change its axial angle according to the angle of the trajectory. In this case, it finds itself in an oblique position in its trajectory with respect to its direction of travel, which is disastrous for both accuracy and power. The pressure level and the weapon's susceptibility to wear may also increase, — the barrel may become copper-plated faster than normal and accuracy may therefore suffer.

Although rifle-caliber weapons have improved significantly in accuracy since the introduction of rifling, the opposite development has also occurred. For example, smoothbore guns are used in tanks, firing tail-stabilized a 25 shells. Accuracy and penetration are good, and the first shot, for example, at an enemy tank, can be fired from about 3,000 meters or even further. A smoothbore barrel can achieve higher muzzle velocities than a rifled barrel, which in this context

E means longer sweep range and better armor penetration, especially

S with small-caliber and arrow ammunition and anti-tank grenades. 3 30

N A bullet can also have grooves called rifling. This is the case, for example, in some shotgun bullets. These are called air rifling, and their purpose is the same as the rifling in the barrel: to cause the bullet to rotate, in this case using air resistance.

Flechette, or arrow projectile or cartridge, is based on arrow-shaped “bullets.” They resemble nails with arrow-shaped fins on the ends to stabilize the flight.

They do not fragment on the target. Arrow projectiles are used in military operations against human targets. They are designed for various weapons: cannons, rifles, pistols and shotguns. Arrow projectiles are particularly effective against various protective equipment such as body armor, flak jackets and helmets. For this reason, the use of arrow projectiles is often limited to official use only. — Sub-caliber arrow projectiles are mainly used against other tanks. Arrow projectiles used in a smooth-bore tank gun (100-125 mm) reach an initial velocity of over 1,500 m/s. The arrow itself is a sharp-tipped “dart” with a diameter of 2-3 cm and a length of over half a meter (dimensions depend on the caliber of the weapon), with small fins at the end that stabilize the flight. The arrow is made of hard and very heavy metal: tungsten carbide or DU (depleted uranium). The penetration of the arrow projectile is based on a very high impact velocity, high kinetic energy and a small impact area. The arrow tip is already inside the vehicle while the tail is still outside. The arrow's high weight in relation to its cross-sectional area maintains its flight speed and allows other ammunition to open fire earlier, and the short flight time forgives errors in distance and advance judgment. The high penetration velocity releases hot fragments from the armor, which cause fires and explosions inside the vehicle, destroying the vehicle's structures and crew. Oxidation of the depleted uranium (DU) during penetration reduces penetration friction and causes an explosion in the vehicle

Q inside. & & 25 = The caliber of the main gun (100-125 mm) of the main battle tank (MBT) is arrow = larger for firing fragmentation and hollow-point grenades and missiles. Therefore, the thin arrow is

E is tied to its socket with a sealing and centering sabot, which is for example made of aluminum

A sealing sleeve consisting of S sectors. The sabot guides the arrow through the tube and opens 2 30 — due to air resistance, detaching from the arrow as the sectors scatter into the foreground. The arrow may penetrate

N several meters of armor steel. Today, a sub-caliber arrow projectile is the main PST projectile against heavily armored targets, such as battle tanks.

The solution according to the invention enables better sealing of projectiles fired with unrifled, smooth barrels against the inner wall of the barrel, thereby allowing the powder pressure created by the charge to be better used to increase the kinetic energy of the projectile.

The solution according to the invention provides a higher initial velocity of the projectile with smaller loads, which enables improved shooting accuracy and increased impact velocity. The solution also enables the use of larger loads without an increasing proportion of the powder pressure escaping through the gap between the projectile and the inner wall of the barrel. For example, it eliminates or reduces the problems encountered in the use of traditional arrow projectiles, such as making sealing sleeves unnecessary. The projectile structure is particularly suitable for — weapons with a smooth barrel, which enables shooting with hard loads.

The projectiles can therefore be both traditional projectiles and arrow projectiles. The speed of the projectiles fired with larger loads is higher, which gives a stable trajectory and a high impact velocity on the target. At the same time, the effect of the rifling on the accuracy of the shot is eliminated, which becomes significant when shooting at long distances. —A rifled barrel also wears out with each shot fired. This wear becomes particularly significant when shooting with large-caliber weapons.

Wear is affected by both the pressure release through the rifling and the friction of the projectile surface against the inner surface of the barrel. The solution according to the invention causes minimal wear on the barrel because the sealing ring can be designed so that it expands radially just right — so that the pressure remains behind the sealing ring, but the pressure does not press the expanded sealing ring unnecessarily hard against the inner surface of the gun barrel. The material and dimensions of the sealing ring are designed for each projectile and load on a case-by-case basis so that the sealing ring functions optimally.

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& 25 — The solution according to the invention comprises a projectile that is fired with a smooth = barrel. When the projectile is in the barrel of the weapon, the powder gas generated during firing = bulges/expands and presses the projectile seal against the inner wall of the barrel. Sealing rings

E can be one or more in a projectile. The use of a smooth barrel allows for earlier

S using higher muzzle velocities and thus extending the shooting range and 2 30 — increasing accuracy, especially at long shooting distances. The projectile can be

N into a rotating motion similar to the movement achieved with grooves by means of the tail design.

The projectile is then a so-called arrow projectile, but the use of the solution according to the invention does not require an arrow projectile, but is suitable for use in all unrifled barrels. When rifling is not required in the barrel of a weapon, the barrel manufacturing process is simplified.

Typically, the solution according to the invention is advantageous for projectiles with a diameter of / inch and larger. 5 In the following, the invention is described in more detail by means of application examples with reference to the accompanying simplified drawings, in which Figure 1 shows a simplified schematic drawing of a preferred projectile according to the invention without sealing rings, Figure 2 shows a simplified schematic drawing of a preferred projectile according to the invention and a sealing ring in a partial view, Figure 3 shows a simplified schematic drawing of another preferred projectile according to the invention and a sealing ring in a partial view, Figure 4 shows a preferred embodiment of a sealing ring in a partial view, and Figure 5 shows another preferred embodiment of a sealing ring in a partial view.

The terms front, front and the like hereinafter refer to a direction or surface corresponding to the direction of flight of the projectile and, correspondingly, the terms rear, rear and the like refer to a direction or surface opposite to the direction of flight of the projectile. & The longitudinal direction refers to the direction of the barrel of the weapon. a 25 o = Figure 1 shows a simplified schematic drawing of a preferred projectile 1 according to the invention = without sealing rings. The projectile has one or

E more. In this embodiment, there are two sealing rings in the projectile and they

For S, two grooves 2 are made in the projectile. The grooves 2 go around the entire projectile 1 2 30 — on its outer circumference and the depth of the grooves is selected according to the sealing ring that will be in it so that

N achieves the best possible seal between the projectile and the inner surface of the gun barrel.

Figure 2 shows a preferred embodiment of the sealing ring 3 of the projectile 1 according to the invention. The sealing ring 3 is mounted in a groove 2, which is preferably rectangular in cross-section. Grooves 2 of other shapes are also possible, but in the simplest case, from the point of view of manufacturing the groove and the seal 3, the groove is — rectangular.

These sealing rings 3 prevent the escape of powder gas to the front of the projectile 1 in the barrel of the weapon from the gap between the projectile and the inner surface of the barrel after the projectile has been fired and enable the projectile to have maximum acceleration and firing speed. Such sealing rings 3 are used in particular when firing with smooth barrels. The sealing rings according to the prior art are rectangular in cross-section or possibly slightly rounded on the side facing the inner surface of the weapon barrel.

The sealing ring 3 according to the embodiment shown in Figure 2 consists of a portion that remains inside the groove 2, the function of which is to hold the sealing ring in place in the groove, and a portion that extends out of the groove, i.e. above the cylindrical surface defined by the outer surface of the projectile. The sealing ring 3 has a lip-like projection 4 that protrudes obliquely out of the groove 2 so that the end 5 of the projection is towards the rear of the projectile 1 and the pressure created by the powder gas. Below the projection 4 is a space/cavity 6 into which the pressure of the powder gas can penetrate — according to arrow 10 — through the gap 7 between the cylindrical outer surface of the projectile 1 and the end 5 of the lip-like projection 4 of the sealing ring after the projectile 1 has been fired. The space/cavity 6 may be located in the portion of the sealing ring that is inside the groove 2 of the sealing ring 3, in the portion of the sealing ring outside the groove of the projectile, or in such a way that part of it is located inside the & groove and part outside the groove. The pressure of the powder gas causes the projection 4 to press against a 25 — the inner surface of the gun barrel, thereby providing a good seal between the projectile 1 and the inner surface of the gun barrel =. This seal keeps the powder gas pressure at the rear of the projectile 1 and = enables the effective use of the powder gas pressure to accelerate the projectile.

E without allowing significant amounts of powder gas pressure to escape from the projectile and

S from the gap between the inner surface of the gun barrel. The pressure of the powder gas therefore causes the sealing ring 3 2 30 — to expand radially in the direction of the radius of the cross-section of the projectile 1 against the gun

N the inner surface of the barrel. The end 5 of the projection 4 of the sealing ring 3 forms a uniform gap 7 in the sealing ring for the powder pressure over the entire circumference of the sealing ring, from which gap the powder pressure enters the space/cavity 6 to bulge the sealing ring radially. When the powder pressure can be better used to increase the speed of the projectile 1, smaller charges can be used to achieve the same speed or, correspondingly, the same charge can be used to obtain a faster moving projectile. Good sealing also enables the use of larger charges, whereby the speed of the projectile 1 can be significantly increased. This enables higher impact velocities on the target and improved shooting accuracy, especially at long shooting distances.

The sealing rings 3 are typically made of copper, copper-bronze alloy, brass or a similar alloy suitable for sealing the projectile. The alloy proportions and — the materials used are selected according to the projectile size and powder pressure. It is essential that the sliding properties and toughness of the material used are sufficient for the function of the sealing ring.

Figure 3 shows another embodiment of the sealing ring 3 according to the invention. — In this embodiment, the sealing ring is also divided into two parts, i.e. the part remaining inside the groove 2, which holds the sealing ring in place, and the part extending out/over the groove, i.e. the cylindrical surface defined by the outer surface of the projectile. In this embodiment, a space/cavity 6 is formed inside the sealing ring 3, into which the pressure of the powder gas enters along the channels 8 formed in the sealing ring. The space/cavity 6 can be located in the part of the sealing ring remaining inside the groove 2 of the sealing ring 3, in the part of the sealing ring outside the projectile groove, or in such a way that part of it is located in the groove and part outside the groove.

In contrast to the embodiment according to Figure 2 shown above, the sealing ring 3 does not have a continuous gap surrounding the entire sealing ring, but separate channels 8 are formed in the sealing ring, along which the gunpowder pressure can enter the space/cavity 6 and bulge the sealing ring radially. Naturally, the channels 8 are placed on the pressurized side of the sealing ring 3, i.e. on the side that faces the rear of the projectile 1 and the resulting gunpowder pressure.

S Figure 4 shows a preferred embodiment of the sealing ring 3, 2 30 according to Figure 3 — which has channels 8 for transferring the powder pressure into the space/cavity 6 inside the sealing ring.

N The sealing ring 3 is depicted from the rear of the projectile, whereby the dotted line 9 depicts the plane of the cylindrical outer surface of the projectile in relation to the sealing ring. Part of the sealing ring 3 therefore remains in the groove 2 and holds the sealing ring in place, and part extends above the cylindrical surface of the projectile. The channels 8 of the sealing ring 3 are in the form of elongated annular openings, which are placed around the entire circumference of the sealing ring above the cylindrical surface formed by the outer surface of the projectile in the area of influence of the powder pressure.

Figure 5 shows another preferred embodiment of the sealing ring 3 according to Figure 3, which has channels 8 for transferring the powder pressure inside the sealing ring to the space/cavity 6. The sealing ring 3 is illustrated from the direction of the rear part of the projectile, whereby the dashed line 9 depicts the plane of the outer surface of the projectile in relation to the sealing ring. Similarly to the embodiment of Figure 4, part of the sealing ring 3 therefore remains in the groove 2 and holds the sealing ring in place, and part again extends above the cylindrical surface of the projectile.

In this embodiment, the channels 8 of the sealing ring 3 are circular openings, which are positioned around the entire circumference of the sealing ring above the cylindrical surface formed by the outer surface of the projectile, in the area affected by the powder pressure.

The method according to the invention for sealing a projectile 1 against the inner surface of a gun barrel consists of the following steps: - one or more grooves 2 extending around the circumference of the projectile are formed on the cylindrical outer surface of the projectile 1, - one or more sealing rings 3 are produced in one or more grooves 2, - a space/cavity 6 is formed in the sealing ring 3, which rotates around the circumference of the entire projectile with the sealing ring, - the pressure of the powder gas is directed into the space/cavity 6 of the sealing ring 3 through the gap 7 or channels 8, & whereby the sealing ring 3 is expanded in the direction of its radius by means of the a 25 — powder pressure entering the space/cavity 6. 2 co = The charge used in connection with the projectile according to the invention does not have to be equal to

E than in prior art projectiles to achieve the same initial velocity

S because the projectile according to the invention is able to better utilize the powder pressure created by the charge used 2 30 — to increase the projectile's velocity. This is a consequence

N because the seal according to the invention keeps the powder pressure better behind the projectile when fired. When using a larger load, when using projectiles according to the prior art, an increasingly larger amount of powder pressure tends to escape from the gap between the projectile and the inner surface of the gun barrel when fired. When using the solution according to the invention, the sealing is improved because the stronger powder pressure presses the seal increasingly strongly against the inner surface of the gun barrel. The invention enables the use of larger loads, thereby obtaining a higher initial velocity and impact velocity for the projectile.

A higher initial velocity results in a more stable trajectory and a higher impact velocity on the target. At the same time, the projectile's accuracy improves compared to a traditional projectile.

This is particularly noticeable at long shooting distances. At the same time, the effects of rifling on the trajectory and accuracy of the projectile are eliminated. The rifling affects the stability of the weapon and tends to turn the barrel/tube of the weapon when the projectile is in the barrel/tube of the weapon. The effects of rifling on accuracy become apparent especially when firing shots that require precision at distant targets. Similarly, part of the pressure of the powder gas can be released through the rifling, so that a rifling-free solution such as the invention makes more efficient use of the resulting pressure.

It is clear to a person skilled in the art that the invention is not limited solely to the examples presented above, but may vary within the scope of the claims presented below.

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Claims (5)

PATENT CLAIMS 1. A sealing ring (3) of a projectile (1) which seals the gap between the projectile (1) and the barrel of a weapon when the weapon is fired, wherein the sealing ring (3) comprises a part of the sealing ring (3) located inside the projectile groove (2) and a part of the sealing ring (3) extending outside the groove (2), characterized in that the sealing ring (3) comprises a space/cavity (6) extending around the entire projectile (1), wherein a slit (7) or several channels (8) open into the space/cavity (6), through which the gunpowder pressure generated during firing enters the space/cavity (6) and that the mouths of the channels (8) or the mouth of the slit (7) are placed in the outer part of the groove (2) of the sealing ring (3) such that said mouths are located in the part of the sealing ring (3) facing the rear of the projectile (1). 2. A sealing ring (3) for a projectile (1) according to claim 1, characterized in that the sealing ring (3) is made of copper, a copper-bronze alloy, brass or a similar alloy metal suitable for sealing a projectile. 3. A projectile (1), characterized in that the projectile comprises one or more sealing rings (3) according to claim 1. 4. A projectile (1) according to claim 3, characterized in that the projectile (1) is a bullet, a grenade or some special projectile, such as a tail-stabilized projectile. 5. A method for sealing a projectile (1), comprising the following steps: - forming one or more grooves (2) extending around the circumference of the projectile (1) on the cylindrical outer surface of the projectile (1), - producing one or more sealing rings (3) in one or more grooves (2), characterised in that & - forming a space/cavity (6) in the sealing ring (3), which rotates with the sealing ring (3) a 25 around the circumference of the entire projectile (1), = - directing the pressure of the powder gas into the space/cavity (6) of the sealing ring (3) through the gap (7) or channels = (8), whereby the sealing ring (3) is expanded in the radial direction of the space/cavity E (6). S 2 N i