Reduced stiffness barrel fired projectile
In various embodiments, a projectile includes a projectile body including a tail portion, a nose portion, a barrel engaging portion between the nose portion and the tail portion, and a metal jacket that defines an exterior of the projectile that surrounds an interior solid core. In one or more embodiments the projectile includes one or more circumferential grooves defined in the interior core portion, each of the one or more circumferential grooves covered by and positioned adjacent to the metal jacket and within the barrel-engaging portion. In various embodiments, during firing of the projectile, the one or more circumferential grooves define a void that allows material of one or more of the metal jacket and interior solid core to displace into the void for reduction in radial stiffness to the projectile in the barrel engaging portion.
1. A projectile comprising:
a projectile body including a tail portion, a nose portion, a barrel engaging portion between the nose portion and the tail portion, and a metal jacket that extends from the tail portion to at least the nose portion and defines an exterior of the projectile that surrounds an interior solid core, the interior solid core including a forward penetrator portion making up a most forward portion of the interior core and a plug portion that is positioned rearward of the penetrator portion, the penetrator portion being composed of a material having a stiffness as measured by Young's modulus greater than 20 Mpsi, and the plug portion being composed of a material having a stiffness as measured by Young's modulus in the range of 10 Mpsi to 30 Mpsi, the portions of the projectile body being arranged along a central longitudinal axis; and
one or more circumferential grooves defined only in the plug portion of the interior core portion, each of the one or more circumferential grooves covered by and positioned adjacent to the metal jacket and within the barrel-engaging portion, each of the one or more circumferential grooves having an axial width and a radial depth, and the axial width is in the range of 0.5 inches to 0.025 inches and the radial depth is in the range of 0.1 inches to 0.0025 inches;
wherein during firing of the projectile, the one or more circumferential grooves define a void that allows material of one or more of the metal jacket and interior solid core to displace into the void for reduction in radial stiffness to the projectile in the barrel engaging portion.
2. The projectile of claim 1 , wherein the nose portion includes a tip portion that forms a spitzer aerodynamic shape for the projectile and that defines a most forward portion for the projectile.
3. The projectile of claim 2 , wherein the metal jacket terminates at a forward portion such that the tip portion is an exposed portion of the penetrator portion not covered by the metal jacket, the tip portion having an exterior surface substantially flush with an exterior surface of the metal jacket and extending from a rearward portion to a forward point of the projectile.
4. The projectile of claim 2 , wherein the metal jacket covers the entirety of the interior core including the tip portion.
5. A projectile comprising:
a projectile body including a tail portion, a nose portion, a barrel engaging portion between the nose portion and the tail portion, and a metal jacket that extends from the tail portion to at least the nose portion and defines an exterior of the projectile that surrounds an interior solid core, the portions of the projectile body being arranged along a central longitudinal axis; and
one or more circumferential grooves defined in the interior core portion and not in the metal jacket, each of the one or more circumferential grooves covered by and positioned adjacent to the metal jacket and within the barrel-engaging portion;
wherein during firing of the projectile, the one or more circumferential grooves define a void that allows material of one or more of the metal jacket and interior solid core to displace into the void for reduction in radial stiffness to the projectile in the barrel engaging portion.
6. The projectile of claim 5 , wherein, each of the one or more circumferential grooves have an axial width and a radial depth, and the axial width is in the range of 0.5 inches to 0.025 inches and the radial depth is in the range of 0.1 inches to 0.0025 inches.
7. The projectile of claim 5 , wherein, each of the one or more circumferential grooves have an axial width and a radial depth, and the axial width is approximately 0.05 inches and the radial depth is approximately 0.005 inches.
8. The projectile of claim 5 , wherein the one or more circumferential grooves extend inwardly 4% to 15% of a diameter of the projectile in the barrel-engaging portion.
9. The projectile of claim 5 , wherein the one or more circumferential grooves possess square or rectangular shape.
10. The projectile of claim 5 , wherein the interior solid core is composed of one or more of aluminum, antimony, beryllium, bismuth, boron carbide, brass, bronze, chromium, cobalt, copper, gold, iridium, iron, lead, magnesium, mercury, molybdenum, nickel, palladium, platinum, rhodium, silicon carbide, silver, steel, tantalum, tellurium, tin, titanium, tungsten, tungsten carbide, depleted uranium, zinc and zirconium, and an alloy.
11. The projectile of claim 5 , wherein the interior solid core includes two or more portions where each portion is composed from a different material.
12. The projectile of claim 11 wherein the interior solid core includes a forward penetrator portion making up a most forward portion of the interior core and a plug portion that is positioned rearward of the penetrator portion.
13. The projectile of claim 12 , wherein the penetrator portion is composed of materials having a high stiffness or lesser malleability than one or more of the metal jacket and the plug portion.
14. The projectile of claim 13 , wherein the penetrator portion is composed of steel and the plug portion is composed of one or more of copper, brass, a copper alloy, and lead.
15. The projectile of claim 5 , wherein the interior solid core is a unitary core composed of a single material.
16. The projectile of claim 5 , wherein the nose portion includes a tip portion that forms a spitzer aerodynamic shape for the projectile and that defines a most forward portion for the projectile.
17. The projectile of claim 16 , wherein the metal jacket terminates at a forward portion such that the tip portion is an exposed portion of the interior core not covered by the metal jacket, the tip portion having an exterior surface substantially flush with an exterior surface of the metal jacket and extending from a rearward portion to a forward point of the projectile.
18. The projectile of claim 16 , wherein the metal jacket covers the entirety of the interior core including the tip portion.
19. The projectile of claim 16 , wherein the tip portion is a polymer tip.
20. A projectile cartridge comprising:
a casing having an upper lip slightly swaged inwardly onto a projectile seated in the casing to form a seal with respect to an interior of the casing; and
a quantity of propellant included along with a primer for initiating detonation of the propellant and for firing the projectile;
wherein the projectile comprises:
a projectile body including a tail portion, a nose portion, a barrel engaging portion between the nose portion and the tail portion, and a metal jacket that extends from the tail portion to at least the nose portion and defines an exterior of the projectile that surrounds an interior solid core, the portions of the projectile body being arranged along a central longitudinal axis; and
one or more circumferential grooves defined in the interior core portion, each of the one or more circumferential grooves covered by and positioned adjacent to the metal jacket and within the barrel-engaging portion;
wherein during firing of the projectile, the one or more circumferential grooves define a void that allows material of one or more of the metal jacket and interior solid core to displace into the void for reduction in radial stiffness to the projectile in the barrel engaging portion.