SHOTSHELL HAVING WAD WITH ENHANCED FIN DEPLOYMENT

Abstract

A shotgun shell has a polymer wad with a forward shot cup portion and a rearward propellant cup, the wad in a casing, shot in the shot cup, propellant in the propellant cup, and a primer. The rearward propellant cup portion having enhanced fin deployment such that the shells are operative with shotguns with no chokes, shotguns with ported chokes, and shotguns with conventional chokes. The forward shot cup portion has axial slits that are sized to preclude shot from passing therethrough while providing sufficient air circulation to provide compaction relief of the shot pack. The enhancement may include gussets on the fins, axially movable disks to engage cam surfaces on the fins and urge them outwardly, and fins that have reduced bending regions compared to prior art wads.

Claims

1. A shotshell cartridge comprising: a casing with a head portion and a primer, a polymer wad positioned in the casing, the wad having a rearward propellant cup portion with a rearward cup interior, a forward shot cup portion with a forward cup interior, a partition separating the rearward propellant cup portion interior from the forward shot cup interior, the propellant cup portion having an interior surface and a bottom; propellant positioned in the propellant cup portion; and shot positioned in the shot cup portion; wherein the propellant cup portion of the wad having a tubular portion with a plurality of axially extending slits defining a plurality of circumferentially arranged fins extending rearwardly and defining a prefiring position, each fin having a gusset extending on the inward side to a central region of the partition, the gusset positioned such that an outward bending of each respective fin to a yield position deforms the respective gusset such that the gusset is elongated inhibiting the fin from returning to the prefiring position and thereby providing a deployed position.

2. The shotshell cartridge of claim 1 wherein the shot cup portion of the wad has a plurality of axially extending linear slit segments that are displaced rearwardly from a forward edge of the wad, plurality of linear slit segments circumferentially spaced around the shot cup portion.

3. The shotshell cartridge of claim 1 wherein the forward cup portion and rearward propellant cup portion of the wad are unitary of a single polymer, and wherein the polymer has a yield point which is exceeded when the cartridge is fired from a choked shotgun whereby each of the plurality of fins extend to at least a yield position and are maintained in their deployed position.

4. The cartridge of claim 1, wherein each of the gussets of the wad partially defines a star shaped projection extending rearwardly from the partition in the interior of the rearward propellant cup.

5. The cartridge of claim 4 wherein when viewed axially, each gusset of the wad is spaced intermediate a pair of the plurality of slits.

6. The cartridge of claim 1 wherein the gusset associated with each fin of the wad extends substantially a length of said fin.

7. A shotshell cartridge comprising: a casing with a head portion and a primer, a polymer wad positioned in the casing, the wad having a rearward propellant cup portion with a rearward cup interior, a forward shot cup portion with a forward cup interior, the propellant cup portion having an interior surface and a base portion; propellant positioned in the propellant cup; and shot positioned in the shot cup portion; wherein the propellant cup portion of the wad having a tubular portion with a plurality of axially extending slits defining a plurality of circumferentially arranged fins extending rearwardly and defining a prefiring position, each fin rotatable outwardly upon the wad exiting a barrel when fired and having a deployed position and a means for retaining each fin in the deployed position, said means for retaining each fin in the deployed position comprises at least one of: a gusset extending on the inward side of each respective fin to a central region of the base portion, and a disk that engages the fins and provides an outward fin opening force when the cartridge is fired

8. The cartridge of claim 7 wherein the means for retaining each fin in the deployed position of the wad comprises a gusset extending on the inward side of each respective fin to a central region of the base portion and wherein an outward bending of each respective fin to a yield position deforms the respective gusset such that the gusset is elongated inhibiting the fin from returning to the prefiring position and thereby retains the fin in the deployed position.

9. The cartridge of claim 7 wherein the means for retaining each fin in the deployed position of the wad comprises a disk that engages the fins and provides an outward fin opening force when the cartridge is fired, the disk having cam engaging surfaces that engage cam surfaces on the plurality of fins when the disk is moved axially.

10. The shotshell cartridge of claim 9, wherein the disk is in the propellant cup portion of the wad and moves forward with respect to the wad when the propellant is ignited.

11. The shotshell cartridge of claim 9, wherein the disk is in the shot cup portion of the wad and moves rearward with respect to the wad, driven by the inertia of the shot.

12. The cartridge of claim 7, wherein the shot cup portion of the wad has a plurality of axially extending slit segments that are displaced rearwardly from a forward edge of the wad.

13. The cartridge of claim 7 wherein the means for retaining each fin in the deployed position of the wad comprises a gusset extending on the inward side of each respective fin to a central region of the base portion and wherein an outward bending of each respective fin to a yield position deforms the respective gusset such that the gusset is elongated inhibiting the fin from returning to the prefiring position and thereby retains the fin in the deployed position, and wherein each of the gussets partially define a star shaped projection extending rearwardly from the partition in the interior of the rearward propellant cup portion and wherein when viewed axially, each gusset is spaced intermediate a pair of the plurality of slits.

14. A shotshell cartridge comprising a wad with a forward shot cup portion and rearward propellant cup, the rearward propellant cup portion having a cup base and a plurality of deployable fins extending rearwardly from the cup base, the fins having a first undeployed position and a second deployed position, the cup base having a star shaped projection with a central projection portion and a plurality of ray portions extending radially outward from a central projection portion oriented toward the plurality of deployed fins, each of the deployable fins movable and retainable at the second deployed position after they are rotated outwardly beyond the second deployed position, the forward shot cup having a sidewall with a plurality of axially extending linear elongate slits extending through the sidewall.

15. The shotshell cartridge of claim 14 wherein the forward slits of the wad are sized such that they do not open far enough for shot pellets to escape therethrough during firing of a shotshell cartridge with the wad therein.

16. The shotshell wad of claim 14, further wherein each ray portion of the wad extends to one of the plurality of deployable fins.

17. The shotshell cartridge of claim 16, wherein each ray of the wad defines a gusset on each respective fin, each gusset having a yield point wherein when the respective fin is rotated to a yield position, the gusset elongates and inhibits the respective fin from returning to the prefiring position.

18. The shotshell cartridge of claim 17, wherein the propellant cup portion of the wad has a sidewall with a length and each gusset extend axially along a respective fine substantially the length of the sidewall.

19. The shotshell cartridge of claim 13 wherein the forward shot cup portion of the wad and the rearward propellant cup portion are unitary.

20. The shotshell cartridge of claim 19 wherein each of gussets of the wad extends substantially a length of its respective fin.

Description

DESCRIPTION OF THE FIGURES

[0022] FIG. 1 is a perspective view of a prior art shotshell wad.

[0023] FIG. 2 is a perspective view of a prior art shotshell wad with fins deployed.

[0024] FIG. 3 is a prior art view of a wad with shot being fired from a shotgun and with the fins of the wad bent forward due to the propellant gas pressure on exit from the barrel and then with the fins retracted to a deployed position during flight.

[0025] FIG. 4 is a prior art view of a wad with shot being fired from a shotgun with a ported choke and with the fins of the wad not deployed due to the barrel pressure drop due to the ported choke and the resulting unstable flight.

[0026] FIG. 5 is an illustration of the barrel pressure drop due to the ported choke.

[0027] FIG. 6 is a cross sectional view of a shotshell with a wad according to an embodiment of the invention.

[0028] FIG. 7 is an end perspective view of the shot cup portion of a wad according to an embodiment of the invention.

[0029] FIG. 8 is an end perspective view of the propellant cup portion of the wad of FIG. 7.

[0030] FIG. 9 is an end elevational view of the propellant cup portion of the wad of FIG. 7.

[0031] FIG. 10 is a side elevational view of the wad of FIG. 7.

[0032] FIG. 11 is a cross sectional view of the wad of FIG. 7.

[0033] FIG. 12 is a perspective end view image of the wad of FIG. 7 with the fins deployed.

[0034] FIG. 13 is a side elevational view image of the wad with the deployed fins of FIG. 12.

[0035] FIG. 14 is perspective view of a wad according to an embodiment of the invention.

[0036] FIG. 15 is an end perspective view of the wad of FIG. 14.

[0037] FIG. 16 is a cross sectional view of the wad of FIG. 14.

[0038] FIG. 17 is a perspective view image of a fired wad as illustrated in FIG. 14 with the fins deployed.

[0039] FIG. 18 is a perspective view of a wad according to an embodiment of the invention.

[0040] FIG. 19 is a perspective view of the wad of FIG. 18 with shot and a disk after the wad and shot leave the muzzle and with the fins deployed.

[0041] FIG. 20 is a perspective view of the wad and shot of FIG. 19 with the shot leaving the shot cup portion of the wad.

[0042] FIG. 21 is a cross sectional view of the wad of FIG. 18.

[0043] FIG. 22 is a cross sectional view of the wad of FIG. 19.

[0044] FIG. 23 is a perspective view of a wad according to an embodiment of the invention.

[0045] FIG. 24 is a perspective shaded view of the wad of FIG. 23.

[0046] FIG. 25 is a cross-sectional view of the wad of FIG. 23.

[0047] FIG. 26 is a cross-sectional view of a wad according to an embodiment of the invention.

[0048] FIG. 27 is an elevational image of a wad as illustrated in FIG. 26 with a cut-away portion of the cup portion illustrating a disk.

[0049] FIG. 28 is a perspective image of the wad of FIG. 27 with the fins deployed.

[0050] FIG. 29 is a cross sectional view of a wad with a dome shaped disk in the propellant cup portion according to an embodiment of the invention.

[0051] FIG. 30 is a cross sectional view of the wad of FIG. 29 with the dome collapsed by the ignition of the propellant creating an outward force on the fins. In this view the wad would still be in the barrel and the fins constrained from deploying.

DETAILED DESCRIPTION

[0052] Referring to FIG. 6, a shotshell cartridge 50 is illustrated in the firing chamber 52 of a barrel 54 of a shotgun 56. The shotshell cartridge 50 is comprised of a wad 60, casing 62, a casing head 64, a primer 68, propellant 70 and shot 72. The wad has a propellant cup portion 78, a partition 80, and a shot cup portion 82.

[0053] The wad 60 is shown in detail in prefiring position or form in FIGS. 7-11. The propellant cup portion has a tubular portion 85 with axially extending linear slits 86 that define circumferentially arranged fins 90 therebetween that extend rearwardly from a bend region 91. The wad has a central axis a and the components of the wad are unitary with one another. The propellant cup portion has an interior 92, a bottom 94 at the partition, side walls 96, an interior surface 97, and an exterior surface 98. Each of the fins has an interior gusset 100 configured as a web extending from a forward portion 104 of the fin to a central region 106 on the bottom 94 of the cup portion. The gussets may be a portion of a star-shaped projection 101 with a plurality of rays 102 extending from a central projection portion 103. The central projection positioned at the center of the bottom inside surface of the propellant cup portion.

[0054] The wad is formed of a polymer such as polyethylene and the gussets are unitarily formed therewith. In the pre fired form or state as shown in FIGS. 6-11, the web provides rigidity to the propellant cup. The web has a mid-portion 112 that is positioned intermediate the gusset portion on the fins and the gusset portion on the bottom. Upon firing, the fins are forced such that the rotate to a yield position as shown in FIG. 3 as the wad leaves the muzzle by the barrel pressure acting within the cup and the gussets are stretched and elongated beyond their yield point such that they do not have any resilience or sufficient resilience to return the fins to their prefired state. Moreover, the gusset has been elongated and thereby inhibits the closing of the fins. Referring to FIGS. 12 and 13, the fins are deployed and are in a relatively fixed deployment position due to the elongated gusset. The initial deployment caused by the expanding propellant gasses just as the wad exits the barrel will typically be at least 90 degrees.

[0055] Referring to FIGS. 14-17, another embodiment is depicted. This wad 110 has a propellant cup portion 112, a shot portion 114, and a partition 116. The fins 118 in this embodiment extend forwardly from a rear edge region 120 of the cup portion 112. Upon firing the shotshell cartridge containing the wad, the propellant in the propellant cup portion ignites and generates expanding propellant gas. The gas pushes outwardly against the fins and when the wad exits the barrel, the fins rotate open about the rear edge region to a deployed state or form as depicted in FIG. 17. The shot portion has slit segments 122 that extend in one direction, axially, and are spaced from the forward edge of the wad. The slits allow air to enter/circulate the shot cup portion to uncompact the shot therein. The slits also permit some circumferential expansion of the shot cup portion after the wad leaves the barrel.

[0056] Referring to FIGS. 18-22, an embodiment of a wad 140 that has a shot cup portion 142, a partition 144, and a propellant cup portion 146 that is abbreviated compared to the propellant cup portion of the previous embodiments. A disk 150 may be positioned in the shot cup portion spaced from the bottom 154 of the cup portion. The fins may have a hinge line or hinge region 158 near the rearward edge portion 162 of the disk 150. Upon firing the inertia of the shot pushes the disk rearward, with respect to the wad traveling forward, where it may engage cam surfaces 162 on the fins, providing a sustained force thereto, urging the fins outwardly about the hinge region 158. Upon exiting the barrel, the sustained force continues and the fins deploy outwardly. The wind provided by the moving wad and shot facilitates complete deployment of the fins, the fins are inhibited from overly rotating rearwardly by a stop surface 162 on the shot cup portion 142. After the shot exits the wad, the wad slows, the fins may partially retract. Apertures 166 provide some air circulation to the shot to facilitate loosening of the shot.

[0057] Referring to FIGS. 23 to 25, a further embodiment is illustrated where a two shot molding process is utilized. The wad 190 comprises a propellant cup portion 192 formed of a first polymer and a shot cup portion 194 formed of a second polymer. The two cup portions are joined at the partition 198 and have a juncture 200 between the different polymers. The propellant cup portion has slits 204 defining fins 206. The shot cup portion having slit segments 210, each with a forward slit end 212 and a rearward slit end 214. The slit segments are displaced from the forward edge 218 of the wad. The two materials may be mechanically connected as well as adhered to each other by the overmolding process. Such overmolding or dual injection molding can create an intermixing of the polymers at the juncture thereby creating a unitary wad. Either cup portion may be molded first. The fins deploy as described above. Although not illustrated in FIG. 25, the propellant cup portion may utilize the gussets as described with respect to FIGS. 6-13 above.

[0058] Referring to FIGS. 26 to 28 a further embodiment of a wad 230 is illustrated utilizing an axially moving disk 232 for effecting an enhancement of the fin deployment. The wad has a propellant cup portion 234, a shot cup portion 236, and a partition 238. The disk 232 has a stem 240 that seats in a central aperture 244 in the partition. Slits 245 define fins 246 extending rearwardly from a bend region 247. When the propellant ignites, the expanding propellant gases drive the disk forwardly and the edges 248 of the disk engage cam surfaces 250 on the fins 246 providing a sustained force thereon urging the fins outward. When the wad escapes the constraint of the barrel, the sustained force deploys the fin. The stem can have catches or interfering portions such that when forced into the aperture 244, it is retained therein. The fins may have gussets as described above.

[0059] Referring to FIGS. 29 and 30, a further wad 260 embodiment of the invention is illustrated and comprises a dome shaped disk 262. The wad 260 has a propellant cup portion 266, a shot cup portion 268, and a partition 270. The propellant cup portion has slits 272 defining fins 276 extending rearwardly and may have gussets as described above with respect to FIGS. 6-13. Upon firing, the dome shaped disk is compressed into the bottom 280 of the propellant cup. The axial compression causes a radially outward sustained force that urges the fins outwardly. When the wad exits the barrel, the sustained force aids in deploying the fins, along with the expanding propellant gases.

[0060] The invention is not restricted to the details of the foregoing embodiment (s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any incorporated by reference references, any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed The above references in all sections of this application are herein incorporated by references in their entirety for all purposes.

[0061] Although specific examples have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement calculated to achieve the same purpose could be substituted for the specific examples shown. This application is intended to cover adaptations or variations of the present subject matter. Therefore, it is intended that the invention be defined by the attached claims and their legal equivalents, as well as the following illustrative aspects. The above described aspects embodiments of the invention are merely descriptive of its principles and are not to be considered limiting. Further modifications of the invention herein disclosed will occur to those skilled in the respective arts and all such modifications are deemed to be within the scope of the invention.