Short round for lightweight automatic weapon
An ammunition cartridge having a cup-shaped casing. The cup-shaped casing has a closed reward end with a rearward diameter and an open forward end having a forward diameter that is larger than the rearward diameter. A sidewall extends between the peripheries of the rearward end and the top end of the casing. The sidewall tapers from the smaller rearward diameter to the larger forward diameter along a length of a hollow interior of the casing that holds a propellant charge.
1. An ammunition cartridge comprising:
a generally cylindrical cup-shaped case having a hollow interior configured to hold a propellant charge, the cup-shaped case including:
a closed rearward end having a rearward diameter;
an open top end having a forward diameter, wherein the forward diameter is greater than the rearward diameter; and
a sidewall extending between a periphery of the closed rearward end and a periphery of the open top end, wherein an outside surface of the sidewall tapers from the rearward diameter to the forward diameter along a length of the hollow interior of the cup-shaped case; and
a top plate attached about a periphery of the top end of the cup-shaped case, wherein the top plate extends over an open end of the cup-shaped case, the top plate further having a raised annular neck defining an aperture aligned with a centerline axis of the cup-shaped case.
2. The cartridge of claim 1 , further comprising:
a projectile disposed within the aperture defined by the raised annular neck of the top plate, wherein at least a portion of the projection extends beyond an upper surface of the top plate.
3. The cartridge of claim 2 , further comprising:
propellant disposed within the hollow interior of the cup-shaped case.
4. The cartridge of claim 1 , wherein the sidewall is disposed at an angle to the centerline axis of the cup-shaped case.
5. The cartridge of claim 1 , further comprising:
a rim extending outward from a connection between the top plate and the open top end of the cup-shaped case about a periphery of the cartridge.
6. The cartridge of claim 5 , further comprising first and second links attached to the rim at opposing locations about the rim.
7. The cartridge of claim 1 , further comprising:
a thinned section formed into the rearward end of the cup-shaped case, the thinned section having a thickness that is less than an average thickness of the rearward end of the cup-shaped case.
8. The cartridge of claim 7 , further comprising:
one or more notches extending outwardly form the thinned section, wherein the notches are formed into the rearward end of the cup-shaped case.
9. The cartridge of claim 7 , wherein the thinned section is aligned with the centerline axis of the cup-shaped case.
10. The cartridge of claim 1 , wherein the rearward end further comprises:
an aperture aligned with the centerline axis of the cup-shaped case; and
a rupture disk covering the aperture.
11. The cartridge of claim 1 , further comprising:
a primer disposed in an aperture in the rearward end of the cup-shaped case.
12. The cartridge of claim 1 , wherein the cup-shaped case and the top plate are integrally formed.
13. The cartridge of claim 1 , wherein at least a portion of a top surface of the top plate is configured to obturate against a rifle barrel.
14. The cartridge of claim 1 , wherein the raised annular neck is configured to obturate against a bullet seat of a rifle barrel.
15. An ammunition cartridge comprising:
a generally cylindrical cup-shaped case having:
a closed rearward end having a rearward diameter, the closed rearward end having an aperture aligned with the centerline axis of the cup-shaped case;
an open top end having a forward diameter, wherein the forward diameter is greater than the rearward diameter; and
a sidewall extending between a periphery of the closed rearward end and the open top end;
a top plate attached about a periphery of the top end of the cup-shaped case, wherein the top plate extends over an open end of the cup-shaped case, the top plate further having a raised annular neck defining an aperture aligned with a centerline axis of the cup-shaped case; and
a rupture disk covering the aperture in the closed rearward end of the cup-shaped case.
16. The cartridge of claim 15 , further comprising:
a projectile disposed within the aperture defined by the raised annular neck of the top plate; and
propellant disposed within an interior of the cup-shaped case.
17. An ammunition cartridge comprising:
a generally cylindrical cup-shaped case having:
a closed rearward end having a rearward diameter;
an open top end having a forward diameter, wherein the forward diameter is greater than the rearward diameter; and
a sidewall extending between a periphery of the closed rearward end and the open top end;
a top plate attached about a periphery of the top end of the cup-shaped case, wherein the top plate extends over an open end of the cup-shaped case, the top plate further having a raised annular neck defining an aperture aligned with a centerline axis of the cup-shaped case; and
a rim extending outward from an interface between the top plate and the open top end of the cup-shaped case about a periphery of the cartridge.
18. The cartridge of claim 17 , further comprising:
a projectile disposed within the aperture defined by the raised annular neck of the top plate; and
propellant disposed within an interior of the cup-shaped case.