The specification and drawings of U.S. Provisional Patent Application No. 62/822,535, filed Mar. 22, 2019, are specifically incorporated herein by reference as if set forth in their entirety.
The present disclosure relates to ammunition, and more particularly, to straight-walled centerfire cartridges. Other aspects also are described.
In various jurisdictions, sportsmen/hunters generally have been limited to using shotguns, muzzleloaders, and handguns during the firearms period of deer season, as higher power centerfire rifle cartridges traditionally have been prohibited for such uses. Some jurisdictions are beginning to loosen such restrictions, however, and are now starting to allow some limited straight-walled, centerfire cartridges to be used during the firearms period for deer season in light of ballistics tests showing bullets fired from straight-walled cartridges generally are slower with less distance. As result, there has been an increased interest in straight-walled centerfire cartridges, especially for use in firearms with tube fed magazines. However, using straight-walled, centerfire cartridges in tube fed/tubular magazines can present problems/issues. For example, when straight-walled, centerfire cartridges are used in tubular/tube fed magazines, the nose of each projectile of the series of cartridges generally will be aligned and can directly interface with the primer/primer cap of the preceding or next cartridge in the magazine, and thus there is a risk that the tip of the projectile could strike and inadvertently activate the primer of the preceding or next cartridge (e.g., if/when the firearm is dropped, bumped, etc.). Such interaction/engagement between the nose of the projectile and the preceding cartridge also may result in damage to the projectile (e.g., potentially affecting the aerodynamic properties/flight characteristics thereof). Accordingly, it can be seen that a need exists for an ammunition cartridge that addresses the foregoing and other related, and unrelated, issues/problems in the art.
In one aspect, the present disclosure provides small-arms ammunition cartridges including a straight-walled, centerfire cartridge for use in firearms with a tubular or tube fed magazine. Such firearms can include rifles, shotguns, or other long guns and/or other firearms having a tubular/tube fed magazines.
The ammunition cartridge generally includes a sabot that is received within the cartridge casing. The sabot is configured to support and locate/align a projectile, and help improve the flight characteristics of the projectile (e.g., distance, accuracy, etc.), as well as shielding the projectile against inadvertent engagement of the projectile with the primer of a next or preceding cartridge. For example, the sabot is configured to protect or extend from the forward end of the cartridge sufficient to engage and seat against a portion, e.g., the head and/or rim of the preceding cartridge in the tubular magazine, with the pointed tip/nose of the projectile substantially protected from directly interfacing with the primer of the preceding cartridge.
The cartridge can include a cartridge body having a generally cylindrical shape with a substantially straight sidewall, and a cavity/chamber defined within and along the cartridge body for receiving a propellant charge therein. The cartridge further has a cartridge base or head formed at a rearward end thereof, and can include a rim defined thereabout. A primer, typically including a primer cap, is substantially centered within the cartridge base or head, extending therethrough. An opening is defined at the opposite end of the cartridge body and generally sized to receive the sabot and projectile therein.
The projectile is received within the opening at a front end of the cartridge body, generally being secured/held therein by the sabot. The projectile will typically include a sub-caliber rifle bullet or other suitable projectile, and will have a body having a base and a forward end generally terminating at a substantially pointed, aerodynamic tip or nose.
The sabot includes a sabot body with a first, rear end and a second, forward, terminal end. The sabot body also generally will have a base portion and one or more substantially cylindrical sidewall portions extending forwardly from the base portion. The sabot body defines a cavity or chamber that is sized and/or configured to receive and hold the projectile within the sabot. For example, the sidewall portion(s) of the sabot body can engage the body of the projectile such that the projectile is nested within the cavity/chamber of the sabot body and is held in place in the cartridge body. The sidewall portion of the sabot body further can include a plurality of features defined therealong (e.g., slots, cuts, etc.) that can help facilitate quick separation of the sabot from the projectile after the sabot and projectile exit the barrel upon firing.
The sabot can have any suitable configuration/construction without departing from the scope of the present disclosure. For example, the sabot can have a multi-piece construction, a weakened construction, a frangible construction, etc., and the sabot further can have one or more area multipliers that facilitate separation of the sabot and the projectile during flight thereof. In one embodiment, the sabot can have a reduced diameter portion/opening that captures or conforms to the projectile about/along its ogive portion/area.
The sabot body generally is configured such that the overall length of the sabot extends beyond the pointed nose/tip of the projectile, by a distance sufficient to substantially shield and maintain the pointed nose/tip in a recessed position spaced from the head and primer of a preceding or next cartridge in the magazine. Thus, the forward, terminal end of the sabot body, rather than the pointed tip/nose of the projectile, will engage and seat against the base/head of the preceding cartridge facilitating loading the cartridges in the tubular magazine in a tight stacked arrangement. The sabot further is configured so that the areas/points of contact or engagement between the terminal end of the sabot and the base of the preceding cartridge are spaced apart from the primer of the preceding cartridge. The sabot thus forms and maintains a gap or space between the pointed tip/nose of the projectile and the primer of the preceding cartridge, e.g., to substantially inhibit or prevent inadvertent engagement of the primer of the preceding cartridge by the point tip/nose of the projectile, and further to substantially reduce the likelihood of or prevent damage to the projectile due to interaction/engagement between the projectile and the preceding cartridge. The sabot generally extends past the forward end of the cartridge at a distance that protects the tip of the projectile while also maintaining industry standards/regulation requirements, such as SAMMI standards, for the total length of the cartridge.
The sabot generally locates and aligns the projectile within the cartridge and with the barrel of the firearm when the cartridge is loaded in the chamber of the firearm. The sabot further can engage the barrel after firing, as the projectile and sabot travel along the barrel, to provide enhanced sealing, and help improve the flight characteristics of the projectile (e.g., increase projectile velocity, accuracy, distance, etc.), such as by imparting a prescribed twist or rotation rate on the projectile, and further can potentially help reduce wear of the barrel of the firearm due to repeated firing, etc.
These and other advantages and aspects of the embodiments of the disclosure will become apparent and more readily appreciated from the following detailed description of the embodiments and the claims, taken in conjunction with the accompanying drawings. Moreover, it is to be understood that both the foregoing summary of the disclosure and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the disclosure as claimed.
The accompanying drawings, which are included to provide a further understanding of the embodiments of the present disclosure, are incorporated in and constitute a part of this specification, illustrate embodiments of this disclosure, and together with the detailed description, serve to explain the principles of the embodiments discussed herein. No attempt is made to show structural details of this disclosure in more detail than may be necessary for a fundamental understanding of the exemplary embodiments discussed herein and the various ways in which they may be practiced.
The following description is provided as an enabling teaching of embodiments of this disclosure. Those skilled in the relevant art will recognize that many changes can be made to the embodiments described, while still obtaining the beneficial results. It will also be apparent that some of the desired benefits of the embodiments described can be obtained by selecting some of the features of the embodiments without utilizing other features. Accordingly, those who work in the art will recognize that many modifications and adaptations to the embodiments described are possible and may even be desirable in certain circumstances. Thus, the following description is provided as illustrative of the principles of the embodiments of the invention and not in limitation thereof, since the scope of the invention is defined by the claims.
As generally shown in
In one embodiment, the cartridge body 20 (or at least portions thereof such as the cartridge base 28) will be formed from metallic materials, such as brass. However, other suitable materials, e.g., other metallic materials, composite or synthetic materials, etc., or combinations thereof, also can be used without departing from the scope of the present disclosure.
The projectile 16 can include any suitable sub-caliber projectile, bullet, etc. The projectile 16 has a body 40 that generally will have an aerodynamic configuration including a pointed nose or tip 42 at a front or terminal end 40B thereof. The body 40 also can have a generally flat end portion 44 at its rear end 40A, as shown in
As additionally shown in
In addition,
In one embodiment, as shown in
The sabot body 50 further is configured such that while the overall length of the cartridge and sabot 14 complies with industry standards, the terminal end of the sabot sidewall portion(s) extends beyond/past the pointed tip 42 of the projectile 16 a distance sufficient to shield the pointed nose/tip 42 by engaging the base/head 128 of a preceding cartridge 112, at locations spaced from/about the primer 132 (
The sabot body 50 further can include a cavity or recess 76 defined its rear end 50A within the sabot base 52, as generally shown in
The sabot body 50 also can be sized/configured such that an exterior surface/portion 51 thereof engages the interior surface of the barrel and/or the rifling defined along the barrel to help improve the flight characteristics of the projectile, for enhanced accuracy, velocity, distance, etc. For example, the exterior surface 51 of the sabot 14 can engage the barrel rifling/interior surface to thereby impart a stabilizing spinning motion on the projectile 16 as it exits the barrel of the firearm.
The sidewall portion 54 of the sabot body 50 further can include a plurality of separation features 78 defined therein/therealong that facilitate separation of the sabot 14 and projectile 16 soon after they exit the barrel upon firing. In one embodiment, as shown in
For example,
Furthermore, in an additional embodiment such as illustrated in
The sabot body 50 further can be formed from various materials including various plastic materials or other suitable synthetics, composites, polymeric, etc. materials that, for example, provide sufficient rigidity, while still allowing for reconfiguration, opening up, etc. of the sabot to facilitate separation of the sabot and the projectile during flight, and/or provide substantial resistance to corrosive materials and/or materials of combustion, such as nitroglycerine, generated or exposed upon firing. As the sabot 14 is generally formed from a softer material than the projectile 16, the sabot 14 can help to reduce wear or other damage to the interior surface of the barrel due to repeated firing. For example, the sabot 14 can protect against/inhibit interaction between the projectile, which can include lead-based materials, the rifling of the barrel of the firearm, and/or the propellant gases, e.g., to help to reduce lead fouling.
The sabot can have any suitable construction/configuration without departing from the scope of the present disclosure. For example, the sabot can have a multi-piece configuration/construction with a plurality of interconnecting pieces or sections that can be designed and/or adapted to break apart or otherwise separate upon the projectile and the sabot exiting the barrel of the firearm. The sabot further can have a segmented construction including a plurality of segments or portions that can be connected to a ring or base portion and interlock/interconnect with each other via flanges/ribs and corresponding slots/grooves formed on opposing sides of the segments/portions, and which segments/portions are configured to separate when the projectile and sabot exit the battel of the firearm. The sabot also can include weakened portions/areas, e.g., that are weakened by spaced axial grooves or notches defined in an inner surface of the cavity/chamber receiving the projectile, which grooves or notches can be sized, dimensioned, or otherwise configured to reduce the tensile strength of portions of the sabot so that a centrifugal force experienced by the sabot body upon exiting the barrel will cause fracture thereof, but not reduce the strength to an extent that such fracture occurs while the projectile and sabot are in the barrel. Still further, the sabot can have a frangible construction including a portion with plurality of cylindrical sections connected together by weakened portions (e.g., including spaced axial grooves or notches that do not extend all the way through the portion of the sabot).
The foregoing description generally illustrates and describes various embodiments of the present invention. It will, however, be understood by those skilled in the art that various changes and modifications can be made to the above-discussed construction of the present invention without departing from the spirit and scope of the invention as disclosed herein, and that it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as being illustrative, and not to be taken in a limiting sense. Furthermore, the scope of the present disclosure shall be construed to cover various modifications, combinations, additions, alterations, etc., above and to the above-described embodiments, which shall be considered to be within the scope of the present invention. Accordingly, various features and characteristics of the present invention as discussed herein may be selectively interchanged and applied to other illustrated and non-illustrated embodiments of the invention, and numerous variations, modifications, and additions further can be made thereto without departing from the spirit and scope of the present invention as set forth in the appended claims.
The present application claims the benefit of previously filed, co-pending U.S. Provisional Patent Application No. 62/822,535, filed Mar. 22, 2019.
Number | Date | Country | |
---|---|---|---|
62822535 | Mar 2019 | US |