ROTATING BAND FOR PROJECTILE

• US 3,786,760 A
• Filed: 06/01/1972
• Issued: 01/22/1974
• Est. Priority Date: 06/01/1972
• Status: Expired due to Term

• Current Assignee: Fritz K. Feldmann
• Original Assignee: Fritz K. Feldmann
• Inventors: Feldmann, Fritz K.
• Primary Examiner(s): Stahl, Robert F.
• Application Number:
  US05/258,558
• Time in Patent Office: 600 Days
• Field of Search: 102/93,94,56
• US Class Current: 102/527
• CPC Class Codes: F42B 14/02 Driving bands; Rotating bands F42B14/04 takes precedence

Abstract

The present invention relates to the use of plastics for rotating bands on projectiles fired from rifled gun barrels. The plastic band is injection molded into a circumferential channel provided in the projectile body. The cross section of the circumferential channel is designed such as to provide a tight gas seal between the plastic rotating band and the projectile body, to assure transfer of spin introduced by the rifling in the gun barrel and to secure the rotating band to the projectile after exit from the muzzle of the gun. The portion of the plastic rotating band protruding beyond the projectile body engraves and is compressed into the rifling groove of the gun barrel, thus obturating the propellant gases and transmitting the spinning motion to the projectile. The plastic rotating band is lighter and costs less than conventional metallic rotating bands and is, in addition, a noncritical war material. Furthermore, its use yields better obturation and reduced barrel wear than is obtained with conventional rotating bands.

Claims

1. A projectile, a groove extending circumferentially of the exterior of the projectile, said groove being recessed below the surface of said projectile and having a generally cylindrical section extending circumferentially of projectile together with generally dovetailed fore and aft shoulder portions defining the sides of said groove, a plastic rotating band located in said groove and extending above the groove surface beyond the diameter of said projectile to engage gun rifling to obturate the propellant gases and to impart spin to the projectile during launch, said cylindrical section having a smooth aft surface covering approximately one half of said cylindrical section, a knurled portion located fowardly of said aft surface, and a shorter smooth surface located forwardly of the knurled surface.

2. A projectile according to claim 1 in which said rotating band comprises an injection molded plastic.

3. A projectile according to claim 1 in which said rotating band comprises injection molded nylon 12.

4. A projectile according to claim 1 in which said rotating band comprises an injection molded high density polyethylene.

5. A projectile according to claim 1 in which said rotating band comprises an injection molded polycarbonate.

6. A projectile according to claim 1 in which said rotating band comprises an injection moldable plastic having an elastic modulus of not less than 1 X 105 psi, a tensile strength of not less than 5,400 psi and an IZOD impact strength (notched) of not less than 4 pounds per inch.

7. A projectile according to claim 1 in which said rotaing band comprises a ductile, elastic plastic having a density of 0.043 pounds per cubic inch, a modulus of elasticity of 34 X 105 psi, and tensile strength of 8,500 psi.