Intermediate article used to form a bullet projectile or component and a finally formed bullet

• US 5,259,320 A
• Filed: 11/10/1992
• Issued: 11/09/1993
• Est. Priority Date: 06/29/1989
• Status: Expired due to Term

• Current Assignee: BB Acquisitions Holding, LLC
• Original Assignee: Barnes Bullets, Inc.
• Inventors: Brooks, Randy C.
• Primary Examiner(s): TUDOR, HAROLD JAY
• Application Number:
  US07/974,319
• Time in Patent Office: 364 Days
• Field of Search: 102/501, 102/507-510, 102/398, 29/1.2-1.23
• US Class Current: 102/509
• CPC Class Codes: B21K 1/025 of bullets
• CPC Class Codes: B21K 21/06 Shaping thick-walled hollow articles, e.g. projectiles
• CPC Class Codes: F42B 12/34 expanding before or on impact, i.e. of dumdum or mushroom type

Abstract

A bullet is manufactured by providing a slug of metal having an end face and applying an axial force against the end face of sufficient magnitude to form an axially outwardly opening first cavity. Thereafter a second force is applied against the first cavity to reform the first cavity into a second cavity having a peripheral edge of a generally scalloped configuration and an interior surface defining tears of alternating triangular flat faces set-off by edges converging toward a blind end of the cavity. The end portion is then contoured into a generally convex curvature which constricts the scalloped peripheral edge and transforms the triangular faces into radially inwardly directed ribs and alternating lines of weakness which, upon bullet impact, control radial expansion and axial tearing of petals formed during impact which creates maximum hydraulic shock in the absence of fragmentation which in turn ensures humane killing of game.

Claims

1. An intermediate article used to form a bullet projectile consisting essentially of a single member formed from a single piece of material defined by axially opposite first and second end portions terminating in respective first and second ends, said first end defining a bottom of said bullet projectile and said second end defining a top thereof, a cavity in said second end portion opening in a direction toward said second end, said second end defining a terminal peripheral edge of said cavity, said terminal peripheral edge being of an undulating configuration, said undulating terminal edge being defined by alternating generally axially upwardly opening concave edge portions and axially upwardly curved convex edge portions, said second end portion also being of a generally outwardly convex configuration converging in a direction toward said second end, and said single member being subject to high pressurization within said cavity upon high velocity object impact whereby said second end portion tears to form petals which impart a mushroom configuration to a finally formed bullet projectile.

2. The intermediate article used to form a bullet projectile as defined in claim 1 wherein said cavity is defined by a plurality of interior surface portions each of a generally triangular configuration, each triangular interior surface portion includes an apex, and said apices generally merge toward a blind end of said cavity.

3. The intermediate article used to form a bullet projectile as defined in claim 1 wherein said cavity is defined by a plurality of interior surface portions each of a generally triangular configuration, each triangular interior surface portion includes an apex, said apices generally merge toward a blind end of said cavity, and each triangular interior surface portion is generally set-off by a pair of converging edges merging at an associated apex and one of said convex edge portions.

4. The intermediate article used to form a bullet projectile as defined in claim 1 wherein said cavity is defined by a plurality of interior surface portions each of a generally triangular configuration, each triangular interior surface portion includes an apex, said apices generally merge toward a blind end of said cavity, and each triangular interior surface portion is generally set-off by a pair of converging edges merging at an associated apex and one of said convex edge portions, and each converging edge terminates at an associated one of said concave edge portions.

5. The intermediate article used to form a bullet projectile as defined in claim 1 wherein said second end portion includes a terminal edge portion deformed inwardly toward a longitudinal axis of said cavity.

6. An intermediate article used to form a bullet component consisting essentially of a single member formed from a single piece of material defined by axially opposite first and second end portions terminating in respective first and second ends, said first end defining a bottom of said bullet component and said second end defining a top thereof, a cavity in said second end portion opening in a direction toward said second end, said second end defining a terminal peripheral edge of said cavity, said terminal peripheral edge being of an undulating configuration, said undulating terminal edge being defined by alternating generally axially upwardly opening concave edge portions and axially upwardly curved convex edge portions, said second end portion also being of a generally outwardly convex configuration, said cavity being defined by a plurality of interior surface portions each of a generally triangular configuration, a first of said triangular interior surface portions each being defined by a first pair of edges each defining a first apex, said first apices merging and defining a blind end of said cavity remote from said undulating terminal edge, a second of said triangular interior surface portions each being defined by a second pair of edges each defining a second apex, and each first triangular interior surface portion being set-off by one of said convex edge portions.

7. An intermediate article used to form a bullet component consisting essentially of a single member formed from a single piece of material defined by axially opposite first and second end portions terminating in respective first and second ends, said first end defining a bottom of said bullet component and said second end defining a top thereof, a cavity in said second end portion opening in a direction toward said second end, said second end defining a terminal peripheral edge of said cavity, said terminal peripheral edge being of an undulating configuration, said undulating terminal edge being defined by alternating generally axially upwardly opening concave edge portions and axially upwardly curved convex edge portions, said second end portion also being of a generally outwardly convex configuration, said cavity being defined by a plurality of interior surface portions each of a generally triangular configuration, a first of said triangular interior surface portions each being defined by a first pair of edges each defining a first apex, said first apices merging and defining a blind end of said cavity remote from said undulating terminal edge, a second of said triangular interior surface portions each being defined by a second pair of edges each defining a second apex, and each second triangular interior surface portion being set-off by one of said convex edge portions.

8. An intermediate article used to form a bullet component consisting essentially of a single member formed from a single piece of material defined by axially opposite first and second end portions terminating in respective first and second ends, said first end defining a bottom of said bullet component and said second end defining a top thereof, a cavity in said second end portion opening in a direction toward said second end, said second end defining a terminal peripheral edge of said cavity, said terminal peripheral edge being of an undulating configuration, said undulating terminal edge being defined by alternating generally axially upwardly opening concave edge portions and axially upwardly curved convex edge portions, said second end portion also being of a generally outwardly convex configuration, said cavity being defined by a plurality of interior surface portions each of a generally triangular configuration, a first of said triangular interior surface portions each being defined by a first pair of edges each defining a first apex, said first apices merging and defining a blind end of said cavity remote from said undulating terminal edge, a second of said triangular interior surface portions each being defined by a second pair of edges each defining a second apex, and each first triangular interior surface portion being set-off by one of said convex edge portions, and each second triangular interior surface portion being set-off by one of said concave edge portions.

9. An intermediate article used to form a bullet component consisting essentially of a single member formed from a single piece of material defined by axially opposite first and second end portions terminating in respective first and second ends, said first end defining a bottom of said bullet component and said second end defining a top thereof, a cavity in said second end portion opening in a direction toward said second end, said second end defining a terminal peripheral edge of said cavity, said terminal peripheral edge being of an undulating configuration, said undulating terminal edge being defined by alternating generally axially upwardly opening concave edge portions and axially upwardly curved convex edge portions, said second end portion also being of a generally outwardly convex configuration, said cavity being defined by a plurality of interior surface portions each of a generally triangular configuration, a first of said triangular interior surface portions each being defined by a first pair of edges each defining a first apex, said first apices merging and defining a blind end of said cavity remote from said undulating terminal edge, a second of said triangular interior surface portions each being defined by a second pair of edges each defining a second apex, and each first triangular interior surface portion being set-off by one of said convex edge portions, and each edge of said first pair of edges merges with a second apex of an associated one of said second triangular interior surface portions.

10. An intermediate article used to form a bullet component consisting essentially of a single member formed from a single piece of material defined by axially opposite first and second end portions terminating in respective first and second ends, said first end defining a bottom of said bullet component and said second end defining a top thereof, a cavity in said second end portion opening in a direction toward said second end, said second end defining a terminal peripheral edge of said cavity, said terminal peripheral edge being of an undulating configuration, said undulating terminal edge being defined by alternating generally axially upwardly opening concave edge portions and axially upwardly curved convex edge portions, said second end portion also being of a generally outwardly convex configuration, said cavity being defined by a plurality of interior surface portions each of a generally triangular configuration, each triangular interior surface portion includes an apex, said apices generally merge toward a blind end of said cavity, and each triangular surface portion includes a relatively shallow concave surface opening toward a longitudinal axis of said cavity.

11. A bullet projectile consisting essentially of a generally elongated one-piece body defined by an exterior surface and axially opposite first and second end portions having respective first and second ends, said first end defining a bottom of said one-piece body and said second end defining a top thereof, an axial cavity in said second end portion having a blind end, said axial cavity being defined by an interior surface at said second end portion, said top including a generally annular terminal edge between said interior and exterior surfaces, said interior and exterior surfaces defining a second end portion wall generally reducing in wall thickness in a direction away from said blind end, a plurality of radially inwardly projecting circumferentially adjacent and longitudinally extending means disposed along an inner peripheral portion of said cavity below said annular terminal edge and above said blind end constricting the radial size of said cavity for controlling radial expansion of petals formed during bullet projectile impact and expansion, and a plurality of circumferentially spaced axially extending weakening means disposed one each between said radial expansion controlling means and extending to said annular terminal edge along said interior surface for controlling axial tearing of the petals during bullet projectile impact and expansion.

12. The bullet projectile as defined in claim 11 wherein each of said means for controlling petal radial expansion is a generally radially inwardly directed rib.

13. The bullet projectile as defined in claim 11 wherein each of said means for controlling petal axial tearing is a generally axially extending line of weakening.

14. The bullet projectile as defined in claim 11 wherein each of said means for controlling petal radial expansion is a generally radially inwardly directed rib, and said ribs are generally of a triangular cross sectional configuration relative to a plane normal to the bullet body axis.

15. The bullet projectile as defined in claim 11 wherein each of said means for controlling petal radial expansion is a generally radially inwardly directed rib, and each of said means for controlling petal axial tearing is a generally axially extending line of weakness.

16. The bullet projectile as defined in claim 11 wherein said second end portion is of a generally outwardly convex configuration.