ARMOUR-PIERCING BULLET SLUG Russian patent published in 2013 - IPC F42B12/02 F42B12/04 F42B30/00 F42B30/02 

FIELD: weapons and ammunition.

SUBSTANCE: armour-piercing bullet slug is made from hard alloy with ultimate compressive strength of more than 4000 MPa, hardness HRA of not lower than 88.5 units, stress intensity factor K_1c of not lower than 8 MPa*m^1/2. Slug has the shape of rotation body in the form of a cone-shaped head part and cylinder-shaped tail part, which are connected to each other. Head part of slug is pointed. Pointed part has cone point rounding of up to 0.33 mm; length of head part is (0.7-2.1)d; slug length is (1.95-5.55)d; tail part has a chamfer or rounding radius of up to 0.15d, where d - diameter of bullet slug is equal to (0.6-0.95)D, where D - bullet gauge. Slug surface has partially or fully the roughness that is not lower than Ra 1.6. Slug material is 6 to 9 wt % of cobalt and/or nickel; tungsten carbide is the rest. Quantity of grains of the main fraction of tungsten carbide with size of 1-2 mcm is at least 60%. Size of individual large grains of tungsten carbide with grain size that exceeds the average size by 4 times is not allowed.

EFFECT: improving piercing performance of slug and after-penetration attack.

1 dwg, 1 tbl