WO2015109302A1

WO2015109302A1 - Pellet for air guns

Info

Publication number: WO2015109302A1
Application number: PCT/US2015/011996
Authority: WO
Inventors: Louis F. Riley; Lee Thomas Phillips
Original assignee: Gamo Outdoor Usa, Inc.
Priority date: 2014-01-20
Filing date: 2015-01-20
Publication date: 2015-07-23
Also published as: US20150204639A1

Abstract

A pellet having an external configuration capable of promoting the aerodynamic and/or terminal (penetration) characteristics of the pellet. The pellet includes a head that defines a projectile tip coinciding with an axis of the pellet, and a raised pattern centered around the projectile tip. The raised pattern comprises a plurality of legs radiating from a center of the raised pattern that coincides with the projectile tip. The raised pattern is defined by at least two tiers that are generally congruent, of different size, and converge at the projectile tip. A smallest of the tiers is superimposed on a largest of the tiers and defines the projectile tip.

Description

PELLET FOR AIR GUNS

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 61/929,167, filed January 20, 2014, the contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] The present invention generally relates to ammunition adapted to be fired from air (gas) operated guns (hereinafter, air guns). More particularly, this invention relates to a pellet having an external configuration capable of promoting the aerodynamic and terminal (penetration) characteristics of the pellet.

[0003] Pellets adapted for use in air guns are typically configured to have a solid head and a hollow skirt. The skirt typically has a frustoconical shape that increases in diameter in the axial direction away from the head, such that the minimum diameter of the skirt is adjacent the head to define a waist between the head and skirt, and the maximum diameter of the skirt is at an end thereof oppositely disposed from the head. The skirt is often intentionally designed to be more malleable than the head to enable the skirt to radially expand when subjected to the high pressure gas used to propel the pellet through the bore of an air gun, such that the outer perimeter of the skirt serves to seal the skirt against the bore to maximize the propulsion effect of the gas as the pellet travels through the bore during firing.

[0004] Aerodynamic and terminal (penetration) characteristics of pellets are of considerable interest, and various pellet designs have been proposed to promote the performance of pellets, including stability, firing accuracy, impact effect, etc. BRIEF DESCRIPTION OF THE INVENTION

[0005] The present invention provides a pellet having an external configuration capable of promoting the aerodynamic and/or terminal (penetration) characteristics of the pellet.

[0006] The pellet includes a head that defines a projectile tip coinciding with an axis of the pellet, and a raised pattern centered around the projectile tip. The raised pattern comprises a plurality of legs radiating from a center of the raised pattern that coincides with the projectile tip. The raised pattern is defined by at least two tiers that are generally congruent, of different size, and converge at the projectile tip. A smallest tier of the tiers is superimposed on a largest tier of the tiers and defines the projectile tip.

[0007] Other aspects and advantages of this invention will be appreciated from the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG. 1 is a perspective view of a pellet in accordance with a nonlimiting embodiment of the invention.

[0009] FIGS. 2 and 3 are top and bottom views of the pellet of FIG. 1

[0010] FIG. 4 is a perspective view of the pellet of FIG. 1 and shows the top of the pellet in more detail. [0011] FIG. 5 is a more detailed side view of the pellet head of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0012] As represented in FIGS. 1 through 5, a pellet 10 in accordance with a particular but nonlimiting embodiment of the invention has a head 12, a hollow frustoconical-shaped skirt 14, and a waist 16 therebetween. The head 12 defines a projectile tip 22 of the pellet 10 that coincides with an axis 34 of the pellet 10, which in the embodiment shown in the drawings is an axis of symmetry. The skirt 14 defines an internal cavity or chamber 15 (FIG. 3) surrounded by the skirt 14. The skirt 14 increases in diameter in the axial direction awayfrom the head 12, such that the minimum exterior diameter of the skirt 14 is adjacent the waist 16, and the maximum diameter of the skirt 14 is at a distal end 18 thereof oppositely disposed from the head 12. The head 12 may have a maximum diameter that is less than the maximum diameter at the end 18 of the skirt 14, such that significant contact does not occur between the head 12 and the surface of an air gun's bore (not shown) as the pellet 10 travels through the bore during firing. The skirt 14 is preferably designed to be more malleable than the head 12 to enable the skirt 14 to radially expand when its chamber 15 is subjected to a high pressure gas that serves to propel the pellet 10 through a bore, such that the outer perimeter of the skirt 14 at its distal end 18 provides a sealing effect between the skirt 14 and the bore surface to maximize the propulsion effect of the gas. Certain other aspects of the pellet 10 may be generally conventional and therefore will not be discussed in any detail here.

[0013] As represented in FIG. 1 , the head 12 of the pellet 10 defines two surfaces 13A and 13B that adjoin to define a periphery 17 that forms the maximum diameter of the head 12. The surface 13A closest to the projectile tip 22 has a generally paraboloid shape that tapers to increase in diameter in the axial direction away from the projectile tip 22 and toward the skirt 14. The surface 13B closest to the skirt 14 has a generally frustoconical shape that tapers to increase in diameter in the axial direction away from the skirt 14 and toward the projectile tip 22. The surface 13A of the head 12 has defined thereon a raised pattern 20 centered around the projectile tip 22 of the head 12. The raised pattern 20 seen in the figures is generally star-shaped, with six legs 24 (FIG. 2) equi-angularly radiating from the center of the pattern 20, which coincides with the projectile tip 22 of the pellet 10. Though the raised pattern 20 is represented as defining six legs 24, the pattern 20 could have fewer or more legs 24, with a preferred range believed to be from three to six legs 24 equi-angularly radiating from the center of the pattern 20.

[0014] The raised pattern 20 and its legs 24 comprise multiple tiers that are generally congruent, of different size, and converge at the tip 22. The raised pattern 20 is represented in the drawings as having two tiers 26 and 28, though it is foreseeable that the pattern 20 could comprise more than two tiers. In the embodiment shown, the larger tier 28 defines the outermost perimeter of the pattern 20 and legs 24 at the surface 13A of the head 12. The larger tier 28 defines a surface 28A that is outwardly offset from the surface 13A of the head 12 to define a step 28B therebetween at the outermost perimeter of the pattern 20. Within each leg 24, the offset of the step 28B (corresponding to the thickness of the larger tier 28) gradually increases in the axial direction towards the tip 22 of the pellet 10. In addition, each surface 28A tapers to a point in the axial direction towards the skirt 14, which is believed to promote the aerodynamic and/or terminal (penetration) characteristics of the pellet 10. As more readily apparent from FIG. 5, the intersections of the surfaces 28A and 28B define offset edges 32.

[0015] The smaller tier 26 is superimposed on the larger tier 28 and defines the pellet tip 22. Within each leg 24, the smaller tier 26 generally has a triangular cross- section defined by two converging side surfaces 26A, each tapering to a point in the axial direction toward the skirt 14. As more readily apparent from FIG. 5, the intersections of the surfaces 26A define offset edges 30, and the distance of each edge 30 from the surface 28A of the larger tier 28 (corresponding to the thickness of the smaller tier 26) gradually increases towards the tip 22 of the pellet 10. The edges 30 defined by the converging surfaces 26A are sharp and pointed in the direction of flight, which is believed to enhance the aerodynamic and terminal (penetration) characteristics of the pellet 10.

[0016] Relative to the contour of the head 12 that would be present in the absence of the raised pattern 20, the smaller and larger tiers 26 and 28 have roughly the same thickness at the tip 22 of the pellet 10 in the axial direction. The thicknesses of the tiers 26 and 28 are intended to culminate in a sharp point at the tip 22, which is believed to further enhance aerodynamic and penetration qualities of the pellet 10.

[0017] The two-tiered, six-legged raised pattern 20 shown in the Figures creates a total of six offset edges 30 defined by the smaller tier 26 (one edge 30 per leg 24) and twelve offset edges 32 defined by the larger tier 28 (two edges 32 per leg 24). The multiple edges 30 and 32 are believed to be capable of promoting terminal performance at the point of impact with a target. For example, if fired from an air gun having barrel rifling, the spin induced in the pellet 10 about its axis 34 and distortion of the raised tiers 26 and 28 and their cutting edges 30 and 32 upon impact will create a jagged cutting edge that will likely produce a larger entry hole in a target and, if used for hunting, a more destructive wound channel, relative to a pellet that lacks the raised pattern 20 but is otherwise identical to the pellet 10. As such, the offset edges 30 and 32 may be referred to as cutting edges 30 and 32. [0018] The portions of the legs 24 defined by the larger tier 28 are represented as having equal radial lengths and as extending from the tip 22 toward the maximum diameter defined by the periphery 17 of the head 12. As evident from FIG. 2, each portion of the legs 24 defined by the larger tier 28 terminates in close proximity to the periphery 17, but does not radially project outside the periphery 17. The portions of the legs 24 defined by the smaller tier 26 also have equal radial lengths and do not radially project outside the periphery 17. However, the portions of the legs 24 defined by the smaller tier 26 are shorter than the portions of the legs 24 defined by the larger tier 28. For example, the embodiment shown in the drawings depict the portions of the legs 24 defined by the smaller tier 26 as extending roughly halfway from the tip 22 to the periphery 17 of the head 12. As such, the raised pattern 20 is entirely defined on the surface 13A of the head 12 that is closer to the projectile tip 22 than the second surface 13B, and the entire raised pattern 20 lies within the periphery 17 when viewed as shown in FIG. 2. It is foreseeable that the portions of the legs 24 defined by the smaller tier 26 could have unequal radial lengths, or the portions of the legs 24 defined by the larger tier 26 could have unequal radial lengths. In addition, though it is possible that the portions of the legs 24 defined by the smaller tier 26 could extend farther and optionally to the periphery 17 of the head 12, the relatively shorter radial lengths of the tiers 26 are believed to promote the desired offset cutting effect of the edges 30 defined by the smaller tier 26.

[0019] While the invention has been described in terms of a specific embodiment, it is apparent that other forms could be adopted by one skilled in the art. For example, the pellet 10 could differ in appearance and construction from the embodiment shown in the Figures, and various processes and materials could be used in the fabrication of the pellet 10. Accordingly, it should be understood that the invention is not limited to the specific embodiment illustrated in the Figures. It should also be understood that the phraseology and terminology employed above are for the purpose of disclosing the illustrated embodiment, and do not necessarily serve as limitations to the scope of the invention. Therefore, the scope of the invention is to be limited only by the following claims.

Claims

CLAIMS:

1 . An air gun pellet comprising:

a head defining a projectile tip coinciding with an axis of the pellet; and a raised pattern centered around the projectile tip, the raised pattern comprising a plurality of legs radiating from a center of the raised pattern that coincides with the projectile tip, the raised pattern being defined by at least two tiers that are generally congruent, of different size, and converge at the projectile tip, a smallest tier of the at least two tiers being superimposed on a largest tier of the at least two tiers and defining the projectile tip.

2. The air gun pellet according to claim 1 , further comprising a skirt having a distal end oppositely disposed from the head, wherein the skirt is hollow and has a frustoconical-shape such that the skirt increases in diameter in an axial direction away from the head, has a minimum exterior diameter adjacent the head to define a waist therebetween, and has a maximum exterior diameter at the distal end thereof.

3. The air gun pellet according to claim 1 , wherein the head of the pellet comprises two adjoining surfaces that define a periphery that forms a maximum diameter of the head.

4. The air gun pellet according to claim 3, wherein a first of the surfaces is closer to the projectile tip than a second of the surfaces, and the first surface has a generally paraboloid shape that tapers to increase in diameter in an axial direction away from the projectile tip.

5. The air gun pellet according to claim 4, wherein the second surface has a generally frustoconical shape that tapers to increase in diameter in the axial direction toward the projectile tip.

6. The air gun pellet according to claim 3, wherein the raised pattern is entirely defined on a first of the surfaces that is closer to the projectile tip than a second of the surfaces.

7. The air gun pellet according to claim 6, wherein the first surface has a generally paraboloid shape that tapers to increase in diameter in an axial direction away from the projectile tip.

8. The air gun pellet according to claim 1 , wherein the smallest and largest tiers gradually increase in thicknesses in the axial direction towards the projectile tip.

9. The air gun pellet according to claim 1 , wherein the plurality of legs radiate equi-angularly from the center of the raised pattern.

10. The air gun pellet according to claim 1 , wherein the plurality of legs of the raised pattern consist of three to six legs.

1 1 . The air gun pellet according to claim 1 , wherein the plurality of legs of the raised pattern consist of six legs.

12. The air gun pellet according to claim 1 , wherein the at least two tiers of the raised pattern consist of the smallest and largest tiers.

13. The air gun pellet according to claim 1 , wherein each of the smallest and largest tiers of the raised pattern define offset edges.

14. The air gun pellet according to claim 13, wherein the offset edges of the raised pattern comprise six edges defined by the smallest tier and twelve edges defined by the largest tier.

15. The air gun pellet according to claim 1 , wherein a portion of each of the legs defined by the smallest tier has sides that converge such that the portion has a triangular cross-section.

16. The air gun pellet according to claim 1 , wherein the smallest and the largest tiers have roughly equal thicknesses at the projectile tip of the pellet in an axial direction thereof.

17. The air gun pellet according to claim 1 , wherein portions of the legs defined by the largest tier have equal radial lengths and extend to a maximum diameter defined by an outermost periphery of the head.

18. The air gun pellet according to claim 1 , wherein portions of the legs defined by the smallest tier have equal radial lengths and do not extend to a maximum diameter defined by an outermost periphery of the head.

19. The air gun pellet according to claim 1 , wherein portions of the legs defined by the largest tier extend to a maximum diameter defined by an outermost periphery of the head, and portions of the legs defined by the smallest tier are shorter and extend roughly halfway to the outermost periphery of the head.

20. A method comprising: placing the pellet of claim 1 in an air gun;

firing the pellet from the air gun to induce a spin in the pellet about the axis thereof; and

impacting a target with the pellet, wherein the smallest and largest tiers of the raised pattern define offset cutting edges and the smallest and largest tiers and the offset cutting edges distort upon impact with the target to increase an entry hole in the target formed by the pellet.