Metal injection molded ammunition cartridge

1. A metal injection molded ammunition cartridge molded as a unitary cartridge comprising:

a unitary molded metal body portion extending from a nose end aperture to a base to form a propellant chamber, wherein the base comprises an upper primer insert portion having a bottom surface, a flash hole positioned in the bottom surface, and a primer recess configured to fit a primer opposite the bottom surface and in communication with the propellant chamber through the flash hole; and

a groove formed in the upper primer insert portion at the bottom surface and surrounding the flash hole.

2. The metal injection molded ammunition cartridge of claim 1 , wherein the molded metal body portion is formed to create to a shoulder that connects to a neck and terminates at the nose end aperture.

3. The metal injection molded ammunition cartridge of claim 1 , wherein the metal composition comprises;

a) 2-16% Ni; 10-20% Cr; 0-5% Mo; 0-0.6% C; 0-6.0% Cu; 0-0.5% Nb+Ta; 0-4.0% Mn; 0-2.0% Si and the balance Fe;

b) 2-6% Ni; 13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65% Nb+Ta; 0-3.0% Mn; 0-3.0% Si and the balance Fe;

c) 3-5% Ni; 15.5-17.5% Cr; 0-0.07% C; 3-5.0% Cu; 0.15-0.45% Nb+Ta; 0-1.0% Mn; 0-1.0% Si and the balance Fe;

d) 10-14% Ni; 16-18% Cr; 2-3% Mo; 0-0.03% C; 0-2% Mn; 0-1% Si and the balance Fe;

e) 10-14% Cr; 0.15-0.4% C; 0-1% Mn; 0-1% Si and the balance Fe; or

f) 16-18% Cr; 0-0.05% C; 0-1% Mn; 0-1% Si and the balance Fe.

4. The metal injection molded ammunition cartridge of claim 1 , wherein the ammunition cartridge is a 5.56 mm, 7.62 mm, 308, 338, 3030, 3006, 50 caliber, 45 caliber, 380 caliber, 38 caliber, 9 mm, 10 mm, 12.7 mm, 14.5 mm, or 14.7 mm ammunition cartridge.

5. The metal injection molded ammunition cartridge of claim 1 , wherein the metal injection molded ammunition cartridge is 20 mm, 25 mm, 30 mm, 40 mm, 57 mm, 60 mm, 75 mm, 76 mm, 81 mm, 90 mm, 100 mm, 105 mm, 106 mm, 115 mm, 120 mm, 122 mm, 125 mm, 130 mm, 152 mm, 155 mm, 165 mm, 175 mm, 203 mm, 460 mm, 8 inch, or 4.2 inch.

6. The metal injection molded ammunition cartridge of claim 1 , wherein the metal composition comprises 102, 174, 201, 202, 300, 302, 303, 304, 308, 309, 316, 316L, 316Ti, 321, 405, 408, 409, 410, 415, 416, 416R, 420, 430, 439, 440, 446 or 601-665 grade stainless steel.

7. The metal injection molded ammunition cartridge of claim 1 , wherein the metal composition comprises brass or a brass alloy.

8. A metal injection molded ammunition cartridge comprising:

a metal injection molded case molded from a metal composition comprising a nose end aperture extending toward a base end to form a portion of a propellant chamber;

a primer recess adapted to accept a primer positioned in the base end; and

a flash hole positioned in the primer recess to pass through the base end into the propellant chamber, and a groove defined at a bottom surface of the base end at an interface of the primer recess and the flash hole, wherein the groove surrounds the flash hole, wherein the metal injection molded ammunition cartridge comprises 2-16% Ni; 10-20% Cr; 0-5% Mo; 0-0.6% C; 0-6.0% Cu; 0-0.5% Nb+Ta; 0-4.0% Mn; 0-2.0% Si and the balance Fe; 2-6% Ni; 13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65% Nb+Ta; 0-3.0% Mn;

0-3.0% Si and the balance Fe; 3-5% Ni; 15.5-17.5% Cr; 0-0.07% C; 3-5.0% Cu; 0.15-0.45% Nb+Ta; 0-1.0% Mn; 0-1.0% Si and the balance Fe; 10-14% Ni; 16-18% Cr; 2-3% Mo; 0-0.03% C, 0-2% Mn; 0-1% Si and the balance Fe; 12-14% Cr; 0.15-0.4% C, 0-1% Mn; 0-1% Si and the balance Fe; 16-18% Cr; 0-0.05% C; 0-1% Mn; 0-1% Si and the balance Fe; or 3-12% aluminum, 2-8% vanadium, 0.1-0.75% iron, 0.1-0.5% oxygen, and the remainder titanium.

9. A metal injection molded ammunition cartridge comprising:

a metal injection molded case molded from a metal composition comprising a base end to form a portion of a propellant chamber;

a primer recess adapted to accept a primer positioned in the base end; and

a flash hole positioned in the primer recess to pass through the base end into the propellant chamber, and a groove defined at a bottom surface of the base end at an interface of the primer recess and the flash hole, wherein the groove surrounds the flash hole, wherein the metal injection molded ammunition cartridge comprises a) 2-16% Ni; 10-20% Cr; 0-5% Mo; 0-0.6% C; 0-6.0% Cu; 0-0.5% Nb+Ta; 0-4.0% Mn; 0-2.0% Si and the balance Fe;

b) 2-6% Ni; 13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65% Nb+Ta; 0-3.0% Mn; 0-3.0% Si and the balance Fe;

c) 3-5% Ni; 15.5-17.5% Cr; 0-0.07% C; 3-5.0% Cu; 0.15-0.45% Nb+Ta; 0-1.0% Mn; 0-1.0% Si and the balance Fe;

d) 10-14% Ni; 16-18% Cr; 2-3% Mo; 0-0.03% C; 0-2% Mn, 0-1% Si and the balance Fe;

e) 12-14% Cr; 0.15-0-4% C; 0-1% Mn, 0-1% Si and the balance Fe;

f) 16-18% Cr; 0-0.05% C; 0-1% Mn, 0-1% Si and the balance Fe; or

g) 3-12% aluminum, 2-8% vanadium, 0.1-0 75% iron, 0.1-0.5% oxygen, and the remainder titanium.

10. The metal injection molded ammunition cartridge of claim 1 , wherein the metal composition comprises one or more selected from stainless steel; ceramic alloys, copper/cobalt/nickel/alloys, tungsten, tungsten carbide, carballoy, ferro-tungsten, titanium, copper, cobalt, nickel, alumina oxide, zirconia or aluminum.

11. The metal injection molded ammunition cartridge of claim 1 , wherein the metal composition comprises:

3-12% aluminum, 2-8% vanadium, 0.1-0.75% iron, 0.1-0.5% oxygen, and the remainder titanium.