JPH04198699A - Obturator for blade-stabilized projectile - Google Patents

Abstract

PURPOSE:To reduce the number of spin of a projectile upon the flight of the same by a method wherein a circumferential recessed groove is formed on the inner peripheral surface of an obturator, in the blade-stabilized projectile provided with the obturator for preventing the leakage of gas upon firing by a gun on the outer peripheral surface of the projectile having blades on the rear part of the same. CONSTITUTION:In a blade-stabilized projectile 1 provided with an obturator 3 for preventing the leakage of gas upon firing by a gun on the outer periphery of the projectile 5 having blades 6 on the rear part of the same, a recessed groove 3a is formed circumferentially on the inner peripheral surface of the obturator 3. When propellant charge 7 is burnt and the blade-stabilized projectile 1 is fired by a gas pressure generated by the combustion, the obturator 3 bites rifles on the inner surface of the bore of the gun and is pressed toward the center of the projectile 5. According to this method, the inner peripheral surface of the obturator 3 is abutted forcibly against the inner bottom surface of the annular groove 5a by a vertical force, however, the recessed groove 3a is formed and, therefore, the obturator 3 is deformed and a pressurizing force, applied on the inner peripheral surface of the obturator 3 and the inner bottom surface of the annular groove 5a, is reduced whereby a frictional force is reduced and the number of spin of the blade-stabilized projectile 1 upon the flight of the same can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an obturator for wing-stabilized bullets that reduces the spin number of the bullet.

(Prior Art) Conventional wing-stabilized bullets have wings at the rear of the bullet, and when fired from a cannon, the bullet slides into contact with the inner circumferential surface of the cannon.

An obturator is provided to prevent the combustion gases of the propellant charge from escaping.

The obturator is formed into a ring shape of metal such as copper or synthetic resin such as nylon, and is fitted into an annular groove formed on the outer peripheral surface of one bullet a as shown in FIG. The inner circumferential surface of the obturator C is formed into a flat surface so as to be in close contact with the inner bottom surface of the annular groove to obtain a high sealing effect.

In addition, when the above-mentioned wing-stabilized bullet is fired from the rifle bore, the outer peripheral surface of the obturator C bites into the rifle on the inside of the gun, generating a vertical force directed toward the center, as shown in Figure 6. In this way, the inner peripheral surface of the obturator C comes into pressure contact with the inner bottom surface of the annular groove.

(Problems to be Solved by the Invention) As mentioned above, wing-stabilized bullets are required to fly at a low spin rate after being fired from the rifle bore. In an obturator formed flat, when the inner peripheral surface is strongly pressed against the inner bottom surface of the annular groove by a vertical force, the frictional force between the two increases and the relative slip of the obturator with respect to one bullet decreases. Put it away.

As a result, when the obturator is rotated by the rifle inside the gun during firing, the bullet is also rotated by friction, so the spin rate of the wing-stabilized bullet increases during flight, and when the shaped charge in one bullet detonates, the Monroe effect occurs. There was a problem that it did not work effectively and its power decreased.

A detonation is when an explosive explodes at a speed higher than the speed of sound and burns quickly.
An explosive reaction accompanied by a shock wave.

The Monroe effect is a phenomenon in which when a conical liner is placed inside a bullet and a shaped explosive charge is detonated, the liner collapses and forms a jet.This jet gradually grows, and after the jet, part of the liner becomes a lump. This means that the shaped explosive is released as a result, increasing the power of the shaped explosive.

This invention was made to improve the above-mentioned problems, and an object of the present invention is to provide an obturator for a wing-stabilized projectile that can reduce the number of spins during flight.

- (Means and effects for solving the problem) In order to achieve the above object, the present invention provides a wing-stabilized bullet having an obturator on the outer periphery of a bullet having wings at the rear to prevent gas leakage when fired by a gun. In this embodiment, a concave groove is formed in the inner peripheral surface of the obturator in the circumferential direction.

As a result, even when the outer circumferential surface of the obturator bites into the rifle on the inside of the gun and receives a vertical force directed toward the center when a wing-stabilized bullet is fired, the obturator deforms due to the groove and absorbs the vertical force, so there is a gap between the obturator and the bullet. The friction force can be reduced.

Furthermore, by providing multiple notches on the inner circumferential surface of the obturator, stress is concentrated on the notches due to the gas pressure acting on the inner circumferential surface, and the obturator breaks from the notch part, so that the obturator can be reliably detached from the bullet after one shot. I can do it.

(Embodiment) An embodiment of the present invention will be described in detail with reference to the drawings shown in FIGS. 1 to 3.

FIG. 1 shows a sectional view of the wing-stabilized bullet mounted on the cartridge. In this figure, 1 is the wing-stabilized bullet, 2 is the cartridge, and 3 is the obturator.

The wing-stabilized bullet 1 houses a shaped explosive charge 4 therein, and its rear portion is inserted into the cartridge 2 through the opening on the tip side of the cartridge 2.

The cartridge 2 is filled almost completely with a propellant charge 7, and a fire tube 8 for igniting the propellant charge 7 is attached to the rear end of the cartridge 2.

On the other hand, an annular groove 5a is formed on the outer peripheral surface of the wing stabilized bullet 1 that protrudes from the tip of the cartridge 2.

The obturator 3 is fitted into this annular groove 5a.

The obturator 3 is formed into a ring shape from a synthetic resin such as nylon, and has an outer circumferential surface tapered to a smaller diameter on the front end side, and an inner circumferential surface at the front end and rear end of the inner bottom surface of the annular groove 5a. It is formed on a flat surface so that it fits tightly.

Further, as shown in FIG. 2, a concave groove 3a is formed in the inner peripheral surface of the obturator 3 in the circumferential direction over the entire circumference.

Next, to explain the operation, when firing the wing-stabilized bullet l from the gun, the wing-stabilized bullet 1 is loaded together with the cartridge 2 into the gun, and the firing charge 7 inside the cartridge 2 is fired by the fire tube 8 of the cartridge 2. ignites.

This causes the propellant charge 7 to burn and generate high pressure gas,
This gas pressure causes the wing-stabilized bullet 1 to be fired forward, but the obturator 3, which prevents combustion gas from leaking, bites into the rifle on the inside of the gun and pressurizes the bullet 5 toward the center.

As a result, the inner peripheral surface of the obturator 3 is pressed against the inner bottom surface of the annular groove 5a by a vertical force.

Since grooves 3a are formed in the inner peripheral surface of the obturator 3 in the circumferential direction, the obturator 3 deforms as shown in FIG. 3 due to the grooves 3a and absorbs vertical force from the outer peripheral direction. The pressing force applied to the inner peripheral surface of the obturator 3 and the inner bottom surface of the annular groove 5a is reduced.

Furthermore, since the frictional force between the inner circumferential surface of the obturator 3 and the inner bottom surface of the annular groove 5a is determined by the vertical force and the friction coefficient, by reducing the vertical force by the eight grooves 3a, the frictional force between the two is reduced.

This increases the relative slip between the obturator 3 and the wing stabilizer 1, so even if the obturator 3 is rotated by the rifle on the inner surface of the gun.

The obturator 3 prevents the wing stabilized bullet 1 from rotating, and the number of spins of the wing stabilized bullet 1 during flight can be reduced.

Note that if a part of the combustion gas is allowed to leak into the groove 3a formed on the inner peripheral surface of the obturator 3, the groove 3a
The inner surface of the obturator 3 and the annular groove 5 are damaged due to the gas leaking inside.
Since the inner bottom surfaces of a are lubricated, the coefficient of friction between the two can be further reduced.

Furthermore, if a plurality of notches 3b are provided in advance on the inner circumferential surface of the obturator 3 at intervals in the circumferential direction as shown in FIG. When released from the restraint on the inner surface of the gun, stress concentrates on each notch 3b against the gas pressure acting from the inner circumferential surface, and the obchelator 3 is ruptured from these notches 3b. The obturator 3 can be reliably removed.

(Effects of the Invention) As described in detail above, the present invention has a structure in which the inner peripheral surface of the obturator prevents gas leakage when firing a wing-stabilized bullet from a gun.
Since grooves are formed in the circumferential direction, even if the outer periphery of the obturator bites into the rifle on the inside of the gun and receives a vertical force toward the center during one firing, the obturator deforms due to the groove and absorbs the vertical force. Therefore, the frictional force between the obturator and the bullet can be significantly reduced.

This improves the relative slippage between the obturator and the bullet, so the rotation of the obturator is less transmitted to the bullet, and the spin rate of the wing-stabilized bullet during flight can be reduced.

In addition, by providing multiple notches on the inner circumferential surface of the obturator, stress is concentrated on the notches due to the gas pressure acting on the inner circumferential surface when one shot is fired, and the obturator breaks from the notch part, making it more reliable than a single shot bullet. Obturator can now be detached.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a wing-stabilized bullet that is an embodiment of the present invention.
FIG. 2 is an enlarged sectional view of the obturator, FIG. 3 is an explanatory diagram of the same operation, FIG. 4 is a perspective view showing another embodiment, and FIGS. 5 and 6 are explanatory diagrams of a conventional obturator. 1... Wing stabilizer bullet, 3... Obturator. 3a...concave groove, 3b...notch. Patent applicant: Defense Agency Technology Research Headquarters (and 1 other person) Agent: Patent attorney Matsuzawa
Figure 6

Claims (3)

[Claims] (1) In a wing-stabilized bullet 1 in which an obturator 3 is provided on the outer periphery of a bullet 5 having wings 6 at the rear to prevent gas leakage when fired by a gun, the inner peripheral surface of the obturator 3 has a concave groove in the circumferential direction. An obturator for wing stabilized bullets formed by 3a. (2) Obturator 3 with grooves 3a formed on the inner peripheral surface
An obturator for a wing-stabilized projectile formed by forming a plurality of notches 3b at intervals in the circumferential direction on the inner peripheral surface of the blade. (3) The obturator according to claims (1) and (2), wherein a part of the gas inside the gun can enter into the groove 3a of the obturator 3.