Method of reducing gun barrel heating
OwnerAndrew W. Sumaninventor
Life of this patent
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Abstract
A cartridge includes a bullet on which there is formed a coating. At least an upper layer of the coating is porous and comprises a thermoset polymer and a filler. The filler may be a dry film lubricant. The cartridge may be used in a gun of the type that has a rifled barrel. A rifled barrel has a bore diameter and a groove diameter. The bullet may have a metal diameter that is less than the groove diameter but slightly greater than the bore diameter. The coated bullet may have a diameter that is greater than or equal to the groove diameter. When fired, the bullet produces less barrel friction and heating than a conventional bullet. The velocity of the coated bullets is greater and the velocity distribution is more narrow compared to uncoated bullets.
Claims20
A bullet, comprising:
- a metal core;
- a coating over a surface of the metal core;
- wherein the coating comprises a porous upper layer;
- and
- the porous upper layer comprises a thermoset polymer and a filler.
A bullet, comprising:
- a metal core;
- and
- a coating on a surface of the metal core;
- wherein the coating comprises an upper layer and is a product of a process comprising:
- applying a powder of particles over the surface, wherein the particles individually comprise a thermosetting resin having a cure temperature and a filler having a melting point above of the cure temperature;
- and
- curing the thermosetting resin to form a thermoset polymer;
- wherein curing causes the particles to sinter, but curing completes without the particles flowing sufficiently to lose their discrete identities.
A loaded gun, comprising:
- a gun loaded with a bullet;
- wherein the bullet has a metal core and a coating on the metal core;
- the coating comprising a thermoset polymer and a filler;
- the gun has a barrel with rifling that includes grooves and lands;
- the barrel has a bore diameter and a groove diameter;
- and
- the metal core has a diameter less than the groove diameter.
Dependencies are inferred from the claim text.