Ammunition and explosives – Projectiles – Composite
Patent
1998-04-03
2000-07-11
Tudor, Harold J.
Ammunition and explosives
Projectiles
Composite
F24B 1402
Patent
active
060856629
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The invention relates to a spin-stabilised projectile, provided with a band. The body of the projectile consists of two main portions which are joined by means of a joint at the stern part of the projectile, where the band is attached to the projectile body. The band is made of a metal alloy which is softer than the material of the projectile body, e.g. a copper alloy.
PRIOR ART
Spin-stabilised projectiles are usually provided with a band of a softer alloy, e.g. copper, for sealing against propellant gases and for imparting a spin to the projectile. When the projectile begins to be advanced through a rifled barrel, grooves are pressed into the band by the rifle ridges which then act as guides for the grooves. As the projectile is accelerated through the bore, the helical rifle ridges force the band and thus the projectile to spin. The indisposition, caused by the spin acceleration, to spinning of the projectile results in great stress between the band and the projectile body. In a conventional fashion, the band is fixed in a groove turned in the projectile body. The band is shrunk by being pressed radially inwards to embossing of the material so as to get a firm grip which is improved by the bottom of the groove being formed with driving flutes, into which the band material is pressed.
Recently, one has begun to use weapons for projectiles acting with kinetic energy. Since this action is dependent on the mass and striking speed of the projectile, these weapons are used together with heavier projectiles and a higher firing speed than in prior-art technique. A higher firing speed is also desired for an increased firing range. Owing to the higher trajectory speed, a higher speed of spinning of the projectile is required for maintained stability. A higher spinning speed is also obtained when older barrels with unchanged rifles are used at an increased firing speed. To make it possible to obtain a higher spinning speed at an unchanged or relatively small increase of the length of the barrel, it is necessary for the spinning of the projectile to accelerate more when driven through the barrel as compared with firing according to earlier technique.
By increasing the mass as well as the spinning acceleration of the projectile, the stresses in the connection between the band and the projectile body, which are caused by the above-mentioned factors, have increased significantly. The stresses have become so great that bands fixed according to prior-art technique have lost their hold and slid in their grooves of the above-mentioned type.
SUMMARY OF THE INVENTION
The object of the invention is to provide a spin-stabilised projectile with a metal band as mentioned by way of introduction. The projectile has, inter alia, the following properties:
This object is achieved by the projectile of the present invention.
A metal band usually is of essentially rectangular cross-section. The boundary surface consists of four surfaces: Inner and outer surface denominated according to the inner and outer diameter of the metal band as well as front and rear flank surface.
The invention suggests that the metal band be fixed by soldering or brazing to the front main portion of the projectile body. In order to accomplish a sufficiently strong connection, both the inner surface of the metal band and as much as possible of its front flank surface are used for soldering or brazing. These surfaces are fixed to the corresponding receiving surfaces of said front main portion, which are designed as a stepped shoulder extending round the stern of the main portion. This shoulder thus comprises a rearwardly directed flank surface and a substantially cylindrical surface extending astern at least as far as the width of the inner surface of the metal band. If the main portion extends further astern than the latter cylindrical surface, the protruding part does not have greater dimensions than to allow the metal band to be slipped onto this part up to the cylindrical surface.
Like in the alternative embodiment, this protruding part
REFERENCES:
patent: 998712 (1911-07-01), McNair
patent: 1408148 (1922-02-01), Tucker
patent: 1444335 (1923-02-01), Cox
patent: 3838497 (1974-10-01), Rizzitano et al.
patent: 3999486 (1976-12-01), Bower
patent: 4532868 (1985-08-01), Gleichaut et al.
patent: 4873416 (1989-10-01), Boder
patent: 5078054 (1992-01-01), Ashok et al.
patent: 5449874 (1995-09-01), Altenau
Forsvarets Forskningsanstalt
Tudor Harold J.
LandOfFree
Spin stabilized projectile with metal band does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Spin stabilized projectile with metal band, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spin stabilized projectile with metal band will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-531166