Patent Application
20220357121
Since the earliest gunpowder activated weapon, the fire lance developed in China in the 10th century, firearms makers have continuously innovated to\increase the accuracy, effectiveness, reliability, and safe operation of firearms weapons. In some instances, such innovations are driven by legislation—for example, laws passed placing restrictions on firearm capacity or structure.
Recently in many jurisdictions, laws have been enacted that limit the capacity of firearm magazines. To adjust to the rule of law, firearms makers have made efforts to create assemblies and other devices that limit or restrict the existing capacity of a cartridge magazine. Prior art attempts include installation of a rivet in the side of the magazine to limit the downward travel of the cartridge follower; installation of a block within the cartridge space of an existing magazine; and/or modification of the followers.
Thus far, all the prior art attempts suffer various disadvantages. For example, they may render the magazine's cartridge feeding capacity unreliable or decrease its lifespan by increasing wear-and-tear on the magazine component parts. Nor are the prior art attempts to limit capacity irreversible, and therefore these modifications remain non-complaint in jurisdictions that require magazine limiting modifications to be substantially permanent.
Therefore, there remains in the art a need for improved capacity-limiting assemblies that provide substantially irreversible modification and thus comply with applicable laws and regulations, without compromising the overall reliability of the magazine.
Included within the scope of the invention is a capacity limiting assembly that provides substantially irreversible alteration of a box magazine to limit its cartridge capacity wherein the box magazine comprises a magazine housing having a vertical dimension YM, a magazine spring having at least 1 coil, and a follower. The assembly includes a limiter body and a lock plate. The limiter body has a top edge engageable with a bottom surface of the follower that is operatively associated with a top of the magazine spring extending into the cartridge reservoir and is configured to be disposed substantially within the at least one coil of the magazine spring. The limiter has a vertical dimension YL that is less than the vertical dimension YM of the magazine housing, and a limiter bottom edge that is engageable to a lock plate. The lock plate of the assembly has a top surface engageable to the bottom surface of the limiter body and bottom surface engageable to the lock plate of the magazine when the lock plate is placed against a bottom edge of the magazine housing. When a top surface of the lock plate is bonded to the limiter body, the limiter substantially irreversibly reduces the capacity of the box magazine.
Also included are magazines fitted with the assembly and related methods of reducing the capacity of magazines.
The foregoing summary and the following detailed description of preferred embodiments of the invention may be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings embodiments which may be presently preferred. The invention is not limited to the precise arrangements and instrumentalities shown. In the drawings:
The invention described herein includes capacity limiting assemblies to provide modification of a box magazine to limit its cartridge capacity, box magazines fitted with such assemblies and methods limiting the capacity of a box magazine. The assembly as described herein can be applied to a box magazine in such a manner that the capacity reduction of the magazine is substantially irreversible. By “substantially irreversible” it is meant that the assembly cannot be removed from the magazine by an average firearms user without significant effort and/or commercial scale tools or equipment without rendering the magazine so damaged as to be useless. By “reduced capacity” or “limited capacity”, it is meant that use of the assembly reduces the number of cartridges that can be inserted into the magazine.
The assembly of the invention is designed to be fitted within a magazine. As is known to persons of skill in the art, the dimensions of magazines may differ depending on the firearm in which it is to be used, the manufacturer and/or other factors. The assembly is adaptable to various magazines, including tubular and integral magazines. For convenience, the assembly is described herein in the context of a generic box-type detachable magazine.
In the exemplary context of a detachable box magazine, the assembly of the invention includes a limiter that includes at least a limiter body and a lock plate or floor plate.
With reference to
Regardless, in the inventive assembly the vertical dimension 14 of the limiter body 12 is always less than the vertical dimension 108 of the magazine housing 102; the relationship between the two dimensions will vary as desired and provides the limiting capacity of the assembly. See,
In various embodiments without limitation, one may construct the assembly so that the vertical dimension of the limiter YL is about 10% to about 90% less than the vertical dimension YM of the magazine housing, about 30% to about 70% less than the vertical dimension YM of the magazine housing and/or about 40%, about 50%, and/or about 60% less than the vertical dimension XM of the magazine housing 102 itself.
In the context of the exemplary limited capacity magazine 100 shown herein, the magazine 100 includes a magazine spring 104 that is vertically disposed within the magazine reservoir 118 defined by the magazine housing 102. The magazine spring 104 contains as many coils 112 as may be necessary to provide a biasing force to feed cartridges from the specific magazine. For example, in a smaller magazine designed for small sized cartridges, the magazine spring may include lesser coils and vice versa. In general, it may be preferred that the magazine spring contains at least 1-33 coils, in some embodiments, at least 10 coils.
The magazine spring 104 is engaged to the follower 106 so that when the spring is biased (contracted) by insertion of cartridges, it provides a pushing force against the follower. In the embodiment shown, a distal end 120 of the magazine spring 104 is attached to the lower surface 114 of the follower 106 by two clips (not shown) extending from the lower surface 114.
However, in an embodiment, the magazine spring needs only to be operatively associated with the follower such that it provides a “push” to the follower to facilitate exit of the cartridge rounds from the magazine. In such embodiment, it may float in position between the follower and the lock plate or floor plate. No direct mechanical attachment or connection is necessarily required between the spring and any other component. In this embodiment, the proximal end 134 of the magazine spring 104 is engaged to the lock plate 24.
This is optional—the spring must only be operatively associated with the lock plate—in many embodiments, for example, the spring merely resting against the lock plate. In the embodiment of the Figures, the upper surface 28 of the lock plate 24 includes a spring securement element 38 that extends from the upper surface 28. The spring securement element 38 has an outer perimeter dimensions to correspond to a ‘loop’ of one coil of the spring 104. The proximal end 134 (i.e., the equivalent of approximately one coil) of the spring 104 is wound around the outer perimeter approximately to secure it to the lock plate. Other manners of engaging the ends of the spring to the relevant component part may also be used, if engagement or connection is desired.
The limiter body 12 is sized and configured to be disposed within coils 112 of the magazine spring 104, that is, more than 90% of the limiter body 12 is sited within an interior coil area 110 defined by the coils 112 of the magazine spring 104. See,
The limiter body has a top edge 18 that is designed to be engaged with the follower 106, preferably the lower surface 114 of the follower 106. As an example, in the embodiment shown in the Figures, the top edge 18 includes an extension 20 that engages with a corresponding slot (not shown) defined by the lower surface 114 of the follower 106 to facilitate smooth and reliable feeding of the cartridges. Other mechanisms by which the follower and the limiter can be engageably attached are well known in the art and are also contemplated as useful in the practice of the assembly.
Continuing with
The specific type of bonding agent 32 selected may be any known or to be developed in the art that provides a substantially permanent or irreversible bond between the material of the lock plate and the floor plate. As an example, when the plates are each formed of a thermoplastic, the bonding agent may be a polyamide polymer adhesive or epoxy. In an embodiment, the lock plate may be formed unitarily with the limiter body, if desired. In the case of such embodiment, there is no additional bonding agent needed.
When the assembly is in the magazine, a bottom surface 34 of the lock plate 24 is disposed against and adjacent to the interior surface 124 of the floor plate 122. In the embodiment shown, a sidewall 126 extends from the interior surface 124 of the floor plate 122 allowing for the reversible slidable engagement of the floor plate 122 to the bottom edge 128 of the magazine housing 102 to close or provide access to the magazine reservoir 118. In the embodiment shown herein, the bottom surface 34 of the lock plate 24 includes a button 36 that extends from the bottom surface and is insertable into a corresponding cavity 130 that is cut through the floor plate 124.
In the embodiment illustrated, when the magazine and assembly are assembled, the floor plate is bonded or otherwise affixed in a substantially irreversible manner to the magazine body and is not removeable. In an embodiment, the floor plate may be welded, melt bonded, cured and/or fusion bonded to the magazine body.
In various embodiments, the lock plate is optional; the limiter may be constructed as part of the floor plate.
Also included in the invention are methods of reducing the capacity of a magazine by fitting it with an embodiment of the assembly described herein.
Any of the component parts described herein may be independently fabricated from any materials developed or presently in the art, for example, polymers, resins, fiberglass, metals, coated materials, and the like. In some embodiment, it may be preferred that the material(s) selected are rigid to discourage attempts to disassemble and/or to increase durability. Any of the component parts described herein, if attached or connected to one another, may be attached/connected by any means, e.g., mechanical connections, adhesives, bonding, welding, fusion bonding, melt bonding, co-curing, etc.
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.
This application claims the benefit under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 63/059,586, filed Jul. 31, 2020, the entire disclosure of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 63059586 | Jul 2020 | US |
