Increased velocity-performance-range bullet

• US 6,244,187 B1
• Filed: 07/01/1999
• Issued: 06/12/2001
• Est. Priority Date: 07/01/1999
• Status: Expired due to Term

• Current Assignee: Federal Cartridge Company (Vista Outdoor Inc.)
• Original Assignee: Federal Cartridge Company (Vista Outdoor Inc.)
• Inventors: Head, Lawrence P.
• Primary Examiner(s): Carone, Michael J.
• Assistant Examiner(s): SEMUNEGUS, LULIT
• Application Number:
  US09/346,182
• Time in Patent Office: 712 Days
• Field of Search: 102/516, 102/514, 102/518-519, 102/507-508
• US Class Current: 102/516
• CPC Class Codes: F42B 12/34 expanding before or on impact, i.e. of dumdum or mushroom type
• CPC Class Codes: F42B 12/78 of jackets for smallarm bullets ; Jacketed bullets or projectiles

Abstract

A mushrooming bullet having a highly improved performance in the retention of the lead core within the bullet jacket subsequent to impact, and in performing effectively over a substantially wider velocity range, the bullet retaining its lead core within its jacket substantially 98-100% of its firings at high velocities, and mushrooming more effectively at lower velocities than conventionally manufactured bullets. The jacket is characterized by a base portion which has a substantially larger interior diameter than its shank portion, and a mouth portion which is substantially softer than its shank portion. The mushrooming of the nose portion of the core and the mouth portion of the jacket is effectively arrested by the harder thick shank portion when the bullet strikes a target, and thereby minimizes the loss of lead from the core. The jacket is further characterized by an annular transition shoulder which extends inwardly from the jacket'"'"'s base portion to its shank portion at an angle to the longitudinal axis of the jacket of at least 7.5 degrees and a radial distance of at least 0.020″, to thereby effectively lock the core within the jacket. The shank portion has a hardness at its rear end of about 145 DPH, which decreases gradually until it joins the mouth portion, at which it has a DPH of about 125 DPH. The mouth portion has a hardness of about 125 DPH at its rear end, which increases gradually to the tip of its mouth at which it has a hardness of about 145 DPH.

Claims

1. An increased velocity-performance-range bullet comprising:

a) a metal bullet jacket having sidewalls defining integral base, shank and mouth portions;

b) said sidewalls of said shank portion and said base portion being of uniformly generally cylindrical exterior size and shape and each defining a cavity therewithin;

c) said base portion sidewall being thin radially relative to said sidewall of said shank portion, and defining an interior cavity of relatively large diameter as compared to said cavity defined by said shank sidewall;

d) said shank portion sidewall having its interior cavity in communication with said base portion cavity and being generally substantially harder than said mouth portion sidewall;

e) said mouth portion sidewall being relatively thin as compared to said shank portion sidewall and defining a mouth portion cavity which tapers inwardly from said shank portion to the mouth of said mouth portion and communicates with said shank portion cavity;

f) a metal core seated within said cavities in non-bonded relation to said jacket and under sufficient pressure to fill said cavities in their entireties; and

g) said relatively thin base portion sidewall joining said relatively thick shank portion sidewall in the form of an inwardly extending annular shoulder which provides an interference of at least 0.020″

.

2. The bullet defined in claim 1, wherein the diameter of said base portion cavity exceeds the diameter of said shank portion cavity by at least 25% of said shank portion cavity diameter.

3. The bullet defined in claim 1, wherein the thickness of said shank portion sidewall exceeds the thickness of said base portion sidewall by at least 80% of said base portion sidewall thickness.

4. The bullet defined in claim 1, wherein said base portion cavity has an axial length of at least 0.06″

.

5. The bullet defined in claim 1, wherein said base portion cavity has a preferred axial length of about 0.125″

.

6. The bullet defined in claim 4, wherein said shank portion sidewall peak hardness is about 20 DPH harder than its mouth portion minimum sidewall hardness.

7. The bullet defined in claim 1, wherein said mouth portion sidewall has a hardness of about 105-145 DPH at the rear end of the mouth portion.

8. The bullet defined in claim 1, wherein said shank portion sidewall has a peak hardness of about 145 DPH and said mouth portion sidewall has a hardness of about 125 DPH at the rear end of the mouth portion.

9. The bullet defined in claim 1, wherein said base portion cavity has a diameter 25-40% larger than the diameter of said shank portion cavity.

10. The bullet defined in claim 1, wherein the diameter of said base portion cavity exceeds the diameter of said shank portion cavity by at least 0.040″

.

11. The bullet defined in claim 1, wherein said shank portion sidewall has a hardness which exceeds the hardness of said minimum mouth portion by about 20 DPH.

12. The bullet defined in claim 1, wherein said shank portion sidewall has a hardness of about 125-165 DPH at its rear end and said mouth portion sidewall has a hardness of about 105-145 DPH at its rear end.

13. The bullet defined in claim 1, wherein said mouth portion sidewall has a hardness of about 125 DPH at its rear end.

14. The bullet defined in claim 1, wherein said shank portion has a peak hardness of about 125-165 DPH at its rear end.

15. The bullet defined in claim 1, wherein said mouth portion sidewall has a hardness of about 105-145 DPH adjacent its intersection with said shank portion sidewall.

16. The bullet defined in claim 1, wherein said shank portion sidewall has a hardness of about 125-165 DPH at its rear end.

17. The bullet defined in claim 1, wherein said mouth portion has a hardness of about 125 DPH at its rear end and said shank portion has a hardness of about 145 DPH at its rear end.

18. The bullet defined in claim 1, wherein said shank portion sidewall is at least 20 DPH harder than the mouth portion minimum sidewall hardness.

19. The bullet defined in claim 1, wherein said shank portion sidewall has a thickness within range of about 0.045-0.070″

and said base portion sidewall has a thickness within a range of about 0.025-0.050″

.

20. The bullet defined in claim 1, wherein shank portion sidewall is generally substantially harder than said mouth portion sidewall and increases in hardness rearwardly from its intersection with said mouth portion.

21. The bullet defined in claim 1, wherein said shank portion sidewall has a diameter at least 25-40% less than the diameter of said base portion cavity.

22. The bullet defined in claim 1, wherein the ratio of the thickness of said shank portion sidewall to the thickness of said base portion sidewall is within the range of about 1.84 to 1.90.

23. The bullet defined in claim 1, wherein said base portion includes an annular transition shoulder extending radially inwardly from a point adjacent said base portion sidewall to said shank portion sidewall, a radial distance slightly less than the thickness of said base portion sidewall.

24. An increased velocity-performance-range bullet comprising:

a) a metal bullet jacket having sidewalls defining integral base, shank and mouth portions;

b) said sidewalls of said shank portion and said base portion being of uniformly generally cylindrical exterior size and shape;

c) said base portion sidewall being relatively thin radially and defining an interior cavity;

d) said shank portion sidewall being relatively thick radially, as compared to said base portion sidewall, and defining an interior cavity which communicates with said base portion cavity;

e) said shank portion sidewall being generally substantially harder than said mouth portion sidewall;

f) said mouth portion sidewall being relatively thin as compared to said shank portion sidewall and defining a mouth portion cavity which tapers inwardly from said shank portion to the mouth of said mouth portion and communicates with said shank portion cavity;

g) an annular transition shoulder carried by said base portion sidewall and extending a radial distance of at least 0.20″

inwardly from said base portion sidewall to the interior surface of said shank portion sidewall; and

h) a metal core seated within said cavities in non-bonded relation to said jacket and under sufficient pressure to fill said cavities in their entireties.

25. The bullet defined in claim 24, wherein said transition shoulder extends radially inwardly a distance exceeding 28% of the radial thickness of said sidewall of said shank portion and constitutes a mechanical lock of the portion of said metal core disposed within said base portion.

26. The bullet defined in claim 24, wherein said transition shoulder extends radially inwardly a distance slightly less than the thickness of said base portion sidewall.

27. The bullet defined in claim 24, wherein said shoulder extends at an angle no less than 7.5 degrees relative to the longitudinal axis of said jacket.

28. The bullet defined in claim 24, wherein the difference between the internal diameter of said sidewall of said base portion and of said sidewall of said shank portion is at least 0.040″

.

29. The bullet defined in claim 24, wherein the difference between the internal diameters of said shank portion sidewall and said base portion sidewall of said shank portion is within the range of 0.040″

and 0.070″

.

30. The bullet defined in claim 24, wherein the axial length of said base portion cavity is at least 0.060″

.

31. The bullet defined in claim 24, wherein the preferred axial length of said base portion cavity is about 0.125″

.

32. The bullet defined in claim 24, wherein the diameter of said base portion cavity exceeds the diameter of said shank portion cavity by at least 25% of the diameter of said shank portion cavity.

33. The bullet defined in claim 24, wherein said differences in the thicknesses of said shank and base portion sidewalls are incorporated within an annular abrupt shoulder extending therebetween.

35. The bullet defined in claim 24, wherein said shank portion sidewall has a hardness which exceeds the minimum hardness of said mouth portion sidewall by about 20 DPH.

34. An increased velocity-performance-range bullet comprising:

(a) a metal bullet jacket having sidewalls defining integral base, shank, and mouth portions;

(b) said sidewalls of said shank portion and said base portion being of uniformly generally cylindrical exterior size and shape, said shank portion sidewall having a thickness within a range of about 0.045-0.070″ and

said base portion sidewall having a thickness within a range of about 0.025-0.050″

;

(c) said mouth portion sidewall being substantially softer than said shank portion sidewall by about 20-40 DPH, said shank portion sidewall having a hardness of about 145 DPH adjacent its rear end;

(d) said sidewalls of said base, shank and mouth portions defining interconnected cavities therewithin;

(e) a metal core seated within said cavities in non-bonded relation to said jacket and under sufficient pressure to fill said cavities in their entireties; and

(f) said relatively thin base portion sidewall joining said relatively thick shank portion sidewall in the form of an inwardly extending angular shoulder which provides an interference of at least 0.020″

.

36. An increased velocity-performance range bullet comprising:

a) a metal bullet jacket having sidewalls defining at least mouth, shank, and base portions which are integral;

b) each of said portions defining a cavity which communicates with the cavities of the others;

c) said sidewall of said shank portion having a peak hardness of about 20 DPH greater than the hardness of said mouth portion at the intersection of said shank sidewall with the rear end of said mouth portion;

d) said mouth portion having a hardness of about 125 DPH at its intersection with said shank portion; and

e) a metal core seated within said cavities in non-bonded relation to said jacket and under sufficient pressure to fill said cavities in their entireties.

39. The improved bullet defined in claim 36, wherein said mouth sidewall has a hardness of about 125 DPH adjacent its rear end.

40. The improved bullet of claim 36, wherein said mouth sidewall has a hardness of about 145 DPH adjacent its mouth.

41. The improved bullet of claim 36, wherein said shank sidewall has a hardness of about 125 DPH adjacent its forward end.

42. The improved bullet of claim 36, wherein said shank sidewall has a hardness of about 145 DPH adjacent its rear end.

37. An increased velocity-performance-range bullet comprising:

(a) a metal bullet jacket having sidewalls defining integral base, shank and mouth portions;

(b) said sidewalls of said shank portion and said base portion defining a cavity within each which communicates with the other said shank portion sidewall having a thickness within a range of about 0.045-0.070″ and

said base portion sidewall having a thickness within a range of about 0.025-0.050″

;

(c) the diameter of said base portion cavity exceeding the diameter of said shank portion cavity by more than 0.040″

;

(d) a metal core seated within said cavities in non-bonded relation to said jacket and under sufficient pressure to fill said cavities in their entireties; and

(e) said relatively thin base portion sidewall joining said relatively thick shank portion sidewall in the form of an inwardly extending angular shoulder which provides an interference of at least 0.020″

.

38. An increased velocity-performance-range bullet comprising:

a) a metal bullet jacket having sidewalls defining at least shank and mouth portions which are integral, the rear end of said mouth portion joining the forward end of said shank portion;

b) each of said portions defining a cavity which communicates with the cavity of the other;

c) said sidewall of said shank portion diminishing in hardness from its rear end toward its forward end;

d) said mouth portion diminishing in its hardness from its forward end toward its rear end;

e) said sidewall shank portion having a hardness of about 125-165 DPH at its rear end and having a hardness of about 105-145 DPH adjacent its forward end;

f) said mouth portion having a hardness of about 105-145 DPH adjacent its rear end and a hardness of about 125-165 DPH adjacent its mouth; and

g) a metal core seated within said cavities in non-bonded relation to said jacket and under sufficient pressure to fill said cavities in their entireties.