Lead-free bullet for use in a wide range of impact velocities

• US 8,186,277 B1
• Filed: 04/10/2008
• Issued: 05/29/2012
• Est. Priority Date: 04/11/2007
• Status: Active Grant

• Current Assignee: Nosler Incorporated
• Original Assignee: Nosler Incorporated
• Inventors: King, Gary D.
• Primary Examiner(s): Lee, Benjamin P
• Application Number:
  US12/100,495
• Publication Number:
  US 20120111220A1
• Time in Patent Office: 1,510 Days
• Field of Search: 102/501, 102/503, 102/507, 102/508, 102/509, D22/116
• US Class Current: 102/507
• CPC Class Codes: F42B 12/34 expanding before or on impact, i.e. of dumdum or mushroom type
• CPC Class Codes: F42B 12/74 of the core or solid body

Abstract

A bullet comprising a lead-free body having a tail section and a nose section. The nose section has an ogived outer surface and a forward terminus. The body further has an opening at the terminus, and a cavity in the nose section. The cavity extends rearward from the opening to an intermediate section of the body. The cavity includes a forward sidewall having at least a generally frusto-conical shape that converges rearward from the opening to a transition area. The cavity further includes a rear sidewall extending rearward from the transition area at a different angle than the forward sidewall.

Claims

1. A bullet comprising a lead-free body having a tail section, a nose section having an ogived outer surface and a forward terminus, an opening at the forward terminus, the opening having a first-cross sectional dimension, and a cavity in the nose section extending rearward from the opening to an intermediate section of the body, wherein the cavity includes a forward sidewall that has at least a generally frusto-conical shape extending from the opening to a second cross-sectional dimension, the forward sidewall converging rearward from the first cross-sectional dimension to the second cross-sectional dimension, and a rear sidewall contiguous with the forward sidewall and extending directly from the second cross-sectional dimension to a third cross-sectional dimension, the rear sidewall diverging rearward from the second cross-sectional dimension to the third cross-sectional dimension.

2. The bullet of claim 1 wherein the body includes longitudinal skives in the forward sidewall.

3. The bullet of claim 1 wherein at least a portion of the rear sidewall converges to form a generally hemispherical end of the cavity.

4. The bullet of claim 1 wherein the lead-free body includes copper.

5. The bullet of claim 1 wherein the lead-free body includes a copper-zinc alloy.

6. The bullet of claim 1 wherein the lead-free body includes copper 210 alloy.

7. The bullet of claim 1 wherein the opening at the terminus is generally circular.

8. The bullet of claim 1, further comprising a separate polymeric tip in the opening projecting forward from the terminus.

9. The bullet of claim 1 wherein at least a portion of the cavity has an hourglass-shape.

10. The bullet of claim 1 wherein the body further comprises a cavity end having a fourth cross-sectional dimension, and wherein the body has a first wall thickness at the second cross-sectional dimension and a second wall thickness at the fourth cross-sectional dimension, the second wall thickness greater than the first wall thickness.

11. A bullet comprising a lead-free body having a tail section, a nose section having an ogived outer surface and a forward terminus, an opening at the forward terminus, and a cavity in the nose section including a forward sidewall extending rearward convergently from the opening toward a transition area, the body having a first wall thickness at the transition area, skives in the forward sidewall, a rear sidewall contiguous with the forward sidewall and diverging rearward from the transition area, and a cavity end, the body having a second wall thickness at the cavity end, the second wall thickness greater than the first wall thickness, wherein the forward sidewall and the rear sidewall are configured to form petals upon impact in animal tissue that remain with the body at impact velocities of approximately 1,800 ft/sec to approximately 3,200 ft/sec.

12. The bullet of claim 11 wherein the transition area is a first transition area, the rear sidewall extends rearward divergently from the first transition area to a second transition area, and at least a portion of the rear sidewall extends rearward convergently to form a generally hemispherical end of the cavity.

13. The bullet of claim 11 wherein the lead-free body includes copper.

14. The bullet of claim 11 wherein the lead-free body includes a copper-zinc alloy.

15. The bullet of claim 11 wherein the lead-free body includes copper 210 alloy.

16. The bullet of claim 11, further comprising a tip in the opening projecting forward from the terminus.

17. The bullet of claim 11 wherein at least a portion of the cavity has an hourglass-shape.

18. The bullet of claim 11 wherein the transition area is a first transition area, and wherein the rear sidewall diverges rearward from the first transition area to a second transition area and converges rearward from the second transition area to the cavity end.

19. A bullet comprising a lead-free body having a tail section, a nose section having an ogived outer surface and a forward terminus, an opening at the forward terminus, the opening having a first-cross sectional dimension, and a cavity in the nose section extending rearward from the opening to an intermediate section of the body, wherein:

the cavity includes a forward sidewall having at least a generally frusto-conical shape extending from the opening to a second cross-sectional dimension, the forward sidewall converging rearward from the first cross-sectional dimension to the second cross-sectional dimension, and a rear sidewall extending directly from the second cross-sectional dimension to a third cross-sectional dimension, the rear sidewall diverging rearward from the second cross-sectional dimension to the third cross-sectional dimension;

the body has a maximum cross-sectional dimension, and the ratio of the first cross-sectional dimension to the maximum cross-sectional dimension is approximately 0.30 to approximately 0.40;

the body has a length and the ratio of the distance of the second cross-sectional dimension rearward of the forward terminus to the body length is approximately 0.20 to approximately 0.25; and

the ratio of the second cross-sectional dimension to the maximum cross-sectional dimension is approximately 0.15 to approximately 0.25.

20. The bullet of claim 19 wherein:

the rear sidewall converges from the second transition area to form a generally hemispherical end of the cavity; and

the ratio of the distance of the third cross-sectional dimension rearward of the forward terminus to the body length is approximately 0.30 to approximately 0.35, and the ratio of the distance of the generally hemispherical end location rearward of the forward terminus to the body length is approximately 0.45 to approximately 0.50.

21. The bullet of claim 20 wherein:

the ratio of the third cross-sectional dimension to the maximum cross-sectional dimension is approximately 0.20 to approximately 0.30; and

the generally hemispherical end of the cavity has a fourth cross-sectional dimension and the ratio of the fourth cross-sectional dimension to the maximum cross-sectional dimension is approximately 0.10 to approximately 0.20.

22. The bullet of claim 19 wherein the body includes copper.

23. The bullet of claim 19 wherein the body includes a copper-zinc alloy.

24. The bullet of claim 19 wherein the body includes copper 210 alloy.

25. The bullet of claim 19 further comprising a tip in the opening that extends forwardly from the terminus.