Ammunition magazine with asymmetric feeding

This disclosure describes systems, methods, and apparatus for a magazine assembly for a firearm, the magazine assembly comprising: an elongated housing, a spring positioned in an interior of the housing, a first and second plate at a proximal end of the housing, at least one follower configured to support one or more cartridges and move or slide within the housing based on a compression and decompression of the spring, one or more feed lips positioned at a distal end of the housing, the one or more feed lips adapted to prevent upward movement of a topmost of the one or more cartridges until a bolt or slide chambers the topmost of the one or more cartridges, and wherein the topmost cartridge is arranged off-center from the bolt of the firearm so as to increase an engagement or overlap between the bolt and the topmost cartridge.

FIELD OF THE DISCLOSURE

The present invention relates to firearms. In particular, but not by way of limitation, the present invention relates to systems and methods for firearm magazines.

DESCRIPTION OF RELATED ART

Bolt action firearms are typically fabricated with a specific cartridge size in mind (e.g., 7.62 mm round, 5.56 mm, 0.22 LR, 0.223 Remington, 0.300 BLK, to name a few non-limiting and common examples). However, manufacturers have started looking to more modular designs where a common stock, receiver, and bottom metal can be combined with barrels and magazines for different cartridge sizes. However, since the bottom metal remains the same across these different modular designs, smaller magazines, e.g., for 5.56 mm, are modified or bulked up to fit the wider bottom metal originally-sized for larger cartridges, such as 7.62 mm or 0.308. While the outer dimension of these adapted magazines increases, the cartridges themselves have a smaller diameter and thus see less overlap, or show less surface area, for the bolt to interact with. This leads to increased chances of malfunctions, for instance, because of insufficient overlap of the bolt face and the topmost round in the magazine. In some cases, a round can get caught between feed ramps, the chamber, and the bolt, after extraction and ejection of the previous round.

Thus, there is a need for a magazine assembly that addresses some of the shortfalls of the present technology where smaller diameter rounds are being used in firearms originally configured for larger diameter rounds.

SUMMARY OF THE DISCLOSURE

In some instances, a user may wish to keep an original configuration of their firearm with minimal changes to the bolt and/or the standard bottom metal, while still having the ability to fire cartridges of both a smaller and a larger diameter. In some cases, the firearm may originally be configured for use with said larger diameter cartridges. Broadly, aspects of the present disclosure relate to an ammunition magazine configured to store and feed cartridges of a smaller caliber into a firearm configured for larger caliber cartridges.

In some cases, the use of smaller cartridges in a firearm, such as a bolt-action rifle, originally configured for larger diameter cartridges may lead to bolt over stoppages, overall length sensitivities, and follower dive, which may adversely impact user experience. To overcome these deficiencies and enhance user experience, aspects of the present disclosure relate to an ammunition magazine with asymmetric feeding, which may serve to maximize bolt face engagement, resist follower dive, and optimize feeding, thus alleviating bolt face overlap issues. In some cases, the asymmetric feeding may be achieved via the use of an offset feedlip geometry, an asymmetric magazine body, or a combination. In some embodiments, the magazine described in this disclosure may be configured for use with short or long action rifles. In some cases, the magazine may be designed and configured for short action rifles comprising Accuracy International Chassis Systems (AICS) pattern bottom metal, and cartridges built on a 0.378 inch case head (e.g., 0.223 Remington) and an overall cartridge length of up to 2.39 inches, although different case head and cartridge length dimensions are contemplated in different embodiments.

Some embodiments of the disclosure may be characterized as a magazine assembly for a firearm, the magazine assembly comprising: an elongated housing comprising a proximal end and a distal end; a spring positioned in an interior of the housing; a first plate removably engaged with the proximal end of the housing; a second plate configured to engage with the first plate and secure the first plate at the proximal end of the housing; at least one follower configured to move or slide within the housing based in part on a compression and decompression of the spring, and wherein the at least one follower is configured to support one or more cartridges; one or more feed lips positioned at the distal end of the housing, wherein the one or more feed lips are adapted to prevent upward movement of a topmost of the one or more cartridges until a bolt or slide chambers the topmost of the one or more cartridges; and wherein the topmost cartridge is arranged off-center from the bolt of the firearm so as to increase an engagement or overlap between the bolt and the topmost cartridge. In some cases, the topmost cartridge may be in a single stack configuration, although different cartridge configurations at the top of the magazine are contemplated in other embodiments.

Other embodiments of the disclosure may also be characterized as a firearm having a magazine well, said firearm comprising: a stock assembly comprising at least an action assembly, the action assembly comprising: one of a bolt or a slide movable between an open and a closed position, a trigger assembly, and a receiver, wherein the receiver is configured for use with cartridges of a first size; a forend assembly comprising at least a barrel, the barrel having a muzzle at its firing end; and a magazine releasably inserted into the magazine well of said firearm and held in place by a magazine latch or release, wherein the magazine is configured to store and feed cartridges of a second size into the firearm, the second size different from the first size. In some embodiments, the magazine may comprise an elongated housing having a distal end and a proximal end, a first plate removably engaged with the proximal end of the housing, a spring, a follower, the follower configured to move or slide within the elongated housing based in part on a compression and decompression of the spring, feed lips positioned at the distal end of the housing, wherein the feed lips are adapted to hold a topmost cartridge of the plurality of cartridges within the magazine until the topmost cartridge is fed into a chamber of the firearm upon action of the bolt or slide of the firearm; and wherein one or more of the elongated housing and feedlips are shaped and positioned to force the topmost cartridge to be off-center from the bolt of the firearm so as to increase an engagement or overlap between the bolt and the topmost cartridge. In some cases, the topmost cartridge may be in a single stack configuration, although different cartridge configurations at the top of the magazine are contemplated in other embodiments.

Other embodiments of the disclosure can be characterized as a method for manufacturing a firearm magazine, the firearm magazine configured to store and feed cartridges of a first size into a firearm originally configured to fire cartridges of a second larger size, said firearm comprising: one of a bolt or a slide movable between an open and a closed position, the method comprising: forming an asymmetrical elongated housing with a proximal end, a distal end, at least one sidewall, and at least one tapered section between the proximal and distal end; affixing a first plate at the proximal end; positioning a follower in the housing; positioning a spring between the follower and the first plate, wherein the spring is configured to move or slide the follower within the housing based on a compression or decompression of the spring; and forming feedlips at the distal end of the elongated housing, wherein the feed lips are adapted to hold a topmost cartridge of a plurality of cartridges within the firearm magazine until the topmost cartridge is fed into a chamber of the firearm upon action of the bolt or the slide of the firearm, and wherein one or more of the feedlips, the elongated housing, and the tapered section are shaped to force the topmost cartridge to be off-center from the bolt of the firearm so as to increase an engagement or overlap between the bolt and the topmost cartridge prior to feeding. In some cases, the topmost cartridge may be in a single stack configuration, although different cartridge configurations at the top of the magazine are contemplated in other embodiments.

DETAILED DESCRIPTION

The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. In the following detailed description, references are made to the accompanying drawings that form a part hereof, and in which are shown by way of illustrations or specific examples. These aspects may be combined, other aspects may be utilized, and structural changes may be made without departing from the present disclosure. Example aspects may be practiced as methods, systems, or apparatuses. The following detailed description is therefore not to be taken in a limiting sense, and the scope of the present disclosure is defined by the appended claims and their equivalents.

For the purposes of this disclosure, and when referencing the magazine, the terms “top end”, upper end”, and “distal” shall refer to a side or direction closer to the firearm; while the term “lower end”, “bottom end”, and “proximal” shall refer to a side or direction away from the firearm. Further, when referencing a direction of intended fire, the terms “front” and “distal” shall refer to a side or direction associated with a direction of intended fire (e.g., inFIG.1, the front or distal side is towards the top of the page), while the terms “back”, “rear”, or “proximal” shall be associated with the intended bracing of the firearm (e.g., inFIG.1, the proximal side is towards the bottom of the page).

As previously indicated, it may be desirable for a user of a firearm to use cartridges of a smaller diameter in a firearm built to handle larger cartridges. However, misfeeding (e.g., a bolt over base malfunction) is a common problem encountered while using existing platforms. This disclosure alleviates these problems by providing a magazine assembly that is configured to increase the engagement, or overlap, between the bolt and the topmost cartridge of the magazine by forcing the topmost cartridge to be slightly off-center (e.g., in a horizontal direction or left-right direction; e.g., out of a plane that runs vertically through a longitudinal axis of the bolt and barrel) from the bolt via the use of an asymmetric body, asymmetric feed lips, or a combination.

Thus, broadly, the present disclosure may be directed towards a magazine assembly configured to store and feed rounds of a first size into a firearm originally configured to fire rounds of a second larger size. For instance, in one example, the present invention may relate to a polymer based magazine capable of storing and feeding 5.56 NATO/0.223 REMINGTON/0.300 BLK cartridges, and configured to fit the MAGPUL PRO 700 chassis designed by MAGPUL Inc., another applicable Aluminum (Al) chassis, the MAGPUL HUNTER 700, also designed by MAGPUL Inc., other compatible REMINGTON 700 actions with appropriate bottom metal, and the MAGPUL HUNTER AMERICAN stock.

FIG.1illustrates a firearm100configured to use an exemplary magazine. In some cases,FIG.1may implement one or more aspects of the figures described herein. The firearm100may include a stock assembly110, a forend assembly128, and a magazine-bolt group102. In some cases, the stock assembly102can include the action assembly, a buttstock, a cheek piece132, and one or more other components. In some cases, the magazine-bolt group102may comprise a bolt106and a magazine104releasably inserted into an action assembly of the stock assembly110. In some cases, the magazine104may attach to the firearm100using a magazine latch or magazine release (hereinafter referred to as a “latch”), or any other means for attaching to/being released from a desired firearm, such as firearm100. In some cases, the latch may be released using a lever or a magazine release to facilitate removal of the magazine104from the firearm100.

In some cases, the action assembly may be removable from the stock assembly102, and can include a trigger assembly, receiver130, and the bolt106among other components. The action assembly may be configured for use with any caliber of round, such as 7.62 mm or 5.56 mm. In some cases, the forend assembly128can include a barrel108, the barrel108having a muzzle at its firing end. Although a bolt-action firearm is illustrated inFIG.1and throughout this disclosure, the novel structures disclosed herein are also applicable to semi-automatic firearms such as AR and AK platforms, to name just two non-limiting examples.

Referring now toFIGS.2through9, and11, the magazine-bolt group102may comprise the magazine104and the bolt106. In some cases, and as described with reference toFIGS.5and6, the magazine104may also comprise an elongated housing107comprising a proximal end109and a distal end111, a first plate, such as a floorplate122, a second plate, such as a lock plate120, at least one follower118, and a spring (not shown). In some embodiments, the floorplate122may be removably engaged with the proximal end of the housing107. Further, the lock plate120may be configured to engage with the floorplate122and secure (or lock) the floorplate122at the proximal end of the housing. In some examples, the lock plate120may protrude through an opening in the floorplate122and may comprise one or more tactile features, such as raised ridges through the magazine floor-plate opening, which may allow for identifying and distinguishing different magazines. In some cases, the follower may move or slide within the housing of the magazine104, through the compression and decompression of the spring (e.g., an accordion spring). Further, the follower118may be configured to support one or more cartridges112. In some cases, the floorplate122may be removable to facilitate maintenance (e.g., cleaning, lubrication) of the magazine and for removal/replacement of its internal components.

In some cases, the magazine104may be loaded with one or more cartridges112. In some cases, the housing107may be adapted to hold any desired number of cartridges (e.g., 5, 10, 30, etc.). Further, the magazine104may be adapted to hold and deliver any desired caliber of rifle or pistol cartridges into the chamber of the firearm100, such as, but not limited to, 0.223 REMINGTON, 5.56 mm NATO, 0.300 BLK, 0.22 LR, 7.62×39 mm, or 7.62×51 mm NATO. In some cases, the cartridges112may be stacked vertically, and arranged in a one, two, four, etc., across configuration. In some embodiments, the cartridges may be staggered, and the cartridges in a particular row of the two or four across configurations may be at different heights (i.e., not level) with respect to one another.

According to an embodiment, the magazine104may be a polymer-based magazine. In some other cases, the magazine104may be made of metal, plastic, carbon fiber, fiberglass, and/or epoxy resin. It should be noted that any suitable material or combination of materials may be used for the magazine. In some cases, the magazine104may be made by injection molding, casting, forming (e.g., bending or stretching), and/or machining (e.g., milling). In some cases, the one or more springs within the magazine may be at a greatest compression when the magazine104is fully loaded.

In some cases, the magazine housing107, also referred to as a casing, may be hollow and elongated. Further, an inside of the magazine housing107shaped to guide the follower118may have a relatively constant length and width along a path of travel of the follower118. As illustrated inFIGS.2and3, the elongated housing107may comprise the narrow lower portion124towards the proximal end109and the upper bulged portion105towards the distal end111, where the narrow lower portion124has a smaller outer width than the upper bulged portion105. In some cases, the outer width of the upper bulged portion105may be based at least in part on an inner width of a magazine well of the firearm. For example, the upper bulged portion105of the magazine casing may be configured to fit within a width of the magazine well of the receiver (e.g., see receiver130inFIG.1). In some cases, for instance, if the diameter of the topmost cartridge is similar or substantially similar to the cartridge diameter originally configured for use with the rifle, the topmost cartridge112supported on the follower118may be substantially aligned with the axis of the barrel108when the magazine104is properly inserted into the magazine well. In some other cases, a centerline of the topmost cartridge112may be misaligned or off-set (e.g., in a horizontal direction) with respect to a centerline of the bolt106, a longitudinal axis passing through a center of the barrel, a centerline of the magazine well, and/or a centerline of the upper bulged portion105, for instance, if the topmost cartridge112has a smaller diameter than cartridges originally configured for use with the firearm100. In other words, the centerline of the topmost cartridge112may be in a vertical plane that is parallel to but laterally offset from a vertical plane passing through the centerline of the bolt and a center of the magazine well.

For the purposes of this disclosure, a centerline may refer to a perpendicular or vertical line (or plane) passing through a geometric center, or a point that is equidistant from the left and right edges (or surfaces), of a respective element (e.g., of a bolt, a topmost cartridge, magazine well, upper bulged portion, narrow lower portion, etc.). In some cases, an offset or misalignment may refer to a displacement, for instance, in a horizontal direction between centerlines of different elements of the magazine and/or firearm. In some embodiments, the displacement may be on the order of a few millimeters (e.g., 1 mm, 2 mm, etc.). Different displacements are contemplated in other embodiments, based on use case, cartridge dimensions, magazine dimensions, bolt dimensions, etc. In some examples, the cross-sections of the topmost cartridge112and the bolt106may be circles, due to their generally cylindrical shapes. In such cases, the centerline of the topmost cartridge may refer to a perpendicular line (or plane) passing through the center of its cross-section circle, and the centerline of the bolt may refer to a different perpendicular line (or plane) passing through the center of its cross-section circle. In this way, the centerline of the topmost cartridge (or bolt) may coincide with a diameter (i.e., vertical and perpendicular diameter) of its cross-section circle. Now, imagine another diameter (i.e., horizontal diameter perpendicular to the vertical diameter) for each of those cross-section circles. Each of these horizontal diameters may intersect the cross-section circle associated with a respective one of the topmost cartridge (or bolt) at two points, where these two points may be equidistant from the centerline of the topmost cartridge (or bolt), since the centerlines of the topmost cartridge (or bolt) coincide with a vertical diameter of their respective cross-section circles. In this case, an offset between the centerline of the topmost cartridge and the centerline of the bolt may refer to a horizontal displacement (e.g., along a y-axis) between the two vertical diameters discussed above.

Similarly, a centerline of the magazine well and a centerline of the upper bulged portion may refer to perpendicular lines (or planes) passing through points that are equidistant in the horizontal direction from the left and right vertical edges (or surfaces) of the magazine well and upper bulged portion, respectively. It should be noted that, a centerline of a narrow lower portion of the magazine may be defined in a similar manner to the centerline of the upper bulged portion and/or magazine well. In some cases, an offset from a centerline of the topmost cartridge and a longitudinal axis passing through a center of the barrel may refer to a displacement in the horizontal direction between the centerline of the topmost cartridge and a vertical plane parallel to and defined by the longitudinal axis of the barrel.

In some cases, the magazine104may comprise the proximal end109(also referred to as a bottom end) and the distal end111(also referred to as a top end). Further, feed lips114(e.g., feed lips114-aand114-b) may be formed at the top end of the magazine104. As shown inFIG.3, the feedlips114-aand114-bmay be arranged on opposing sides of the elongated housing107and may be shaped and positioned above the upper bulged portion105. In some aspects, the feed lips114may be designed to keep cartridges held within the magazine104until the cartridges112are fed from the magazine104, such as by action of the firearm's bolt106. In other words, the feed lips114may be adapted to prevent upward movement of a topmost of the one or more cartridges until the bolt106or a slide (not shown) chambers the topmost of the one or more cartridges. In some cases, the topmost cartridge112may be arranged off-center from the bolt106of the firearm (e.g., firearm100inFIG.1) so as to increase an engagement or overlap between the bolt and the topmost cartridge112.

In some cases, cartridges112may be fed from the magazine104to the firearm100prior to and after the firearm is fired. As the cartridges112are fed, the cartridges112within the magazine104advance towards the feed lips114of the magazine. In some cases, such feeding typically occurs after a cartridge112is fired, and the bolt106of the firearm100is retracted. In some cases, the bolt106of the firearm100may be retracted by action of the user, or using recoil kinetic energy of the firearm, or through any other means. Moving the bolt106forward and into the chamber may strip the topmost cartridge112forward out of the magazine104and into the chamber. In some cases, this force may be known as the stripping force. Although this disclosure primarily discusses a bolt, in other embodiments, a slide can play a similar role (e.g., in pistols utilizing aspects of this disclosure).

Where a magazine storing smaller cartridges is used in a firearm designed for use with larger cartridges, the magazine may include an upper bulge105having dimensions matched to the firearm's magazine well, and a narrow lower end124having smaller dimensions reflecting the smaller cartridges in the magazine104. In some cases, the feed lips114-aand114-bof the magazine104may be asymmetric with respect to one another (e.g., seeFIGS.3,8,9, and10), for instance, by placing them at different heights. Additionally or alternatively, the feed lips may have different dimensions (e.g., length or curvature) or feedlip geometry. In some other cases, the feed lips114-aand114-bmay be made of materials with different rigidity or elasticity, for instance, one feedlip may be composed of steel and the other of a polymer, to name just one non-limiting example. In yet other cases, the feedlips114-aand114-bmay not be equidistant from the centerline of the bolt, further illustrated inFIGS.10and13B. For instance, inner surfaces of the feedlips114-aand114-bmay be at different horizontal distances from the centerline of the bolt and/or upper bulged portion105. Additionally or alternatively, the outer surfaces of the feedlips114-aand114-bmay be at different horizontal distances from the outer edge or surface of the upper bulge105, as also shown inFIGS.10and13B. In some other cases, the points at which the inner and/or outer surfaces of a first feedlip (e.g., feedlip114-a), and the points at which the respective inner and/or outer surfaces of the second feedlip (e.g., feedlip114-b) intersect the housing may not be equidistant from the centerline of the bolt, upper bulge, etc. In some other cases, one feedlip (e.g., feedlip114-a) may be wider than the other feedlip (e.g., feedlip114-b).

Additionally or alternatively, in some examples, the magazine body may be asymmetric relative to the narrow lower portion124(see, especiallyFIGS.3and9). For instance, the elongated housing107may be shaped such that the upper bulged portion105is asymmetric with respect to the narrow lower portion124. As an example, and as illustrated in at leastFIGS.3,4,10, and13, the left and right vertical edges of the narrow lower portion124may be at different distances from the respective left and right vertical edges of the upper bulged portion105, leading to an asymmetry between the upper bulge105and the narrow lower end124. In some embodiments, the centerline of the narrow lower portion124may coincide with a centerline of the cartridges supported on the follower, for instance, in a single-stack magazine. In such cases, the centerline of the cartridges (including the topmost cartridge) may be off-set (or off-center) from the centerline of the upper bulged portion (i.e., since the centerlines of the upper bulge and narrow lower end may not coincide). Further, as shown inFIG.4, the tapered portions116of the housing of the magazine (i.e., magazine body) may be asymmetric. This asymmetry may exist in two fashions: a left and right side of the taper may be asymmetric, and/or the taper at the top and bottom of the upper bulge105may be asymmetric.

In some embodiments, the elongated housing107may comprise first and second distal tapers arranged on opposing sides of the housing and extending at first and second distal angles, respectively, in an upward direction from the upper bulged portion105, further described in relation toFIG.10. In some cases, the first distal angle may be different from the second distal angle. Similarly, the elongated housing107may also comprise first and second proximal tapers arranged on opposing sides of the housing and extending at first and second proximal angles, respectively, between the upper bulged portion105and the narrow lower portion124, where the first and second proximal angles may be different, further described in relation toFIG.10. It should be noted that, the first proximal and distal tapers may be arranged on a first side of the elongated housing, while the second proximal and distal tapers may be arranged on a second side of the elongated housing, where the first and second sides are different (or opposing) sides of the housing. In some embodiments, a length of the first proximal and distal tapers may be different. Additionally or alternatively, the first proximal and distal angles may be different. In some embodiments, a length of the second proximal and distal tapers and/or the second proximal and distal angles may also be different.

FIG.10is a rear view of the magazine104illustrating the asymmetric feed lips114-aand114-barranged on opposing sides of the elongated housing (i.e., magazine body). Further, as illustrated, magazine104may comprise an asymmetrical magazine body, since the left and right vertical edges (or surfaces) of the narrow lower portion124may be at different distances from the respective left and right vertical edges (or surfaces) of the upper bulged portion105. Accordingly, there may exist an asymmetry between the upper bulge105and the narrow lower end124of the magazine body. In some cases, the centerlines of the upper bulge and narrow lower portion may not coincide. Furthermore, in some embodiments, the centerline of the narrow lower portion124may coincide with a centerline of the cartridges supported on the follower, for instance, in a single-stack magazine. It should be noted that other cartridge stacking configurations (e.g., dual stack, staggered, etc.) are contemplated in different embodiments.

In some examples, one or more tapered sections may also impart asymmetry to the magazine body or housing. For instance, as shown, first and second proximal tapers (e.g., tapers defined by first and second proximal angles126-aand126-b) may extend at first and second proximal angles, respectively, between the narrow lower portion124and the upper bulged portion105of the magazine104. Contrary to typical magazine designs, however, the tapered portions of the magazine body may be substantially asymmetric with respect to the narrow lower portion124and the upper bulged portion105of the magazine. In other words, the left and right sides of the lower tapered portion of the magazine body may be at different angles (i.e., proximal angle126-aand proximal angle126-bare different) with respect to the narrow lower end124, and the left and right sides of the upper tapered portion may be at different angles (i.e., distal angle126-cand distal angle126-dare different) with respect to the upper bulged portion105of the magazine104. In some aspects, the upper bulged portion105may be slightly skewed in one direction (e.g., to the right of the page inFIG.10), due to different first and second proximal angles and/or different first and second distal angles. In some circumstances, the first proximal and distal angles126-aand126-c, respectively, may be of equal or approximately equal value (e.g., 45 degrees, 50 degrees, 60 degrees, etc.). Further, the second proximal and distal angles126-band126-d, respectively, may be of equal or approximately equal value (e.g., 30 degrees, 35 degrees, etc.).

In some examples, the centerline of the upper bulge105(e.g., see centerline1320inFIG.13) may be configured to coincide with the centerline of the magazine well, which may allow the magazine104to securely fit within the magazine well of the receiver. Further, the centerline of the magazine well may be the same as the centerline of the bolt106. In other words, the centerlines of the upper bulge105, the magazine well, and the bolt106may all coincide. Further, a longitudinal axis passing through a center of the barrel may also coincide with the centerline of the bolt106. However, a centerline of the topmost cartridge may not be aligned with this centerline and may therefore be offset from the bolt when viewed from above, further described in relation toFIG.12. In some examples, a centerline of the narrow lower portion124may not coincide with one or more of the centerline of the upper bulge portion105, the magazine well, and the bolt106.

As further described with reference toFIG.12, the centerline of topmost cartridge112of the magazine104may be offset (e.g., horizontally or along a horizontal plane) relative to the centerline of the magazine104, the bolt106, or both. It should be noted that, each centerline may be associated with or defined by a vertical plane passing through the horizontal center of a respective one of the topmost cartridge, bolt, etc., where the centerline is parallel to and a part of said vertical plane. Said another way, a centerline or centerplane of an element may be equidistant (horizontally) from the left and right edges (or surfaces) of the respective element (e.g., topmost cartridge or bolt). In some cases, such a configuration may serve to enhance feeding of the cartridges112into the chamber of the rifle by increasing the bolt-cartridge overlap or engagement, as well as minimizing follower dive.

FIG.12is a top view of the magazine-bolt group102illustrating the asymmetric placement of the topmost cartridge112with respect to the bolt106. In some cases, the bolt106may be sized for engaging cartridges of a first caliber and may successfully extract a cartridge of this size even when the cartridges are aligned with a centerline of the bolt. However, issues such as jamming or misfeeding may arise while attempting to use cartridges of a second and smaller caliber with such a bolt (i.e., when topmost cartridge112and a centerline of the bolt align, the bolt106may not properly engage the topmost cartridge112in the magazine104). In order to mitigate this, the feedlips (e.g., feedlips114-aand114-binFIG.11) may be arranged such that the topmost cartridge112is offset from a centerline of the upper bulge105and also from a centerline of the bolt106prior to feeding. This offset along with positioning the topmost cartridge higher up in the firearm may enable a greater area of overlap between the bolt106and the topmost cartridge112, as shown inFIG.13B, thereby reducing the chances of the bolt failing to extract the topmost cartridge112. In some circumstances, magazines may comprise one or more magazine stops (or simply, mag stops or stops) configured to interact with a portion of the magazine well. These mag stops may set a stopping point of the magazine when inserted upward into the magazine well. According to aspects of the current disclosure, these mag stops may be positioned lower on the magazine104, as compared to a typical magazine (said another way, a top surface of a magazine stop may be arranged further from a top of a higher of the two feedlips than this same distance in a traditional magazine without asymmetric feedlips). In this way, the mag stop in magazine104may be positioned further away, in a vertical direction, from a top of the feedlips, as compared to a vertical distance between a mag stop and a top of the feedlips in typical magazines. This allows for the topmost cartridge to be positioned higher in the magazine well relative to the bolt than in traditional systems. Further, positioning the mag stop lower on the magazine104, as compared to a typical magazine, may also allow the magazine to be inserted higher up within the magazine well of the firearm. Accordingly, the topmost cartridge112may also be positioned higher up in the firearm, which may allow for a greater degree of overlap between the bolt and the topmost cartridge.

As shown, the left surface of the topmost cartridge112(toward a center of the page) is a distance128-aaway from the left surface of the bolt106along the y-axis, and the right surface of the topmost cartridge112is a distance128-baway from the right surface of the bolt106along the y-axis. In some embodiments, the distance128-amay be shorter than distance128-b, as also seen via the reproduction of distance128-aon the right surface for comparison only. Accordingly, there may exist an offset between the centerline of the bolt106and the centerline of the topmost cartridge112in the magazine since the longitudinal surfaces of the topmost cartridge112are not equidistant from the respective longitudinal surfaces of the bolt106. In some examples, since the topmost cartridge112in the magazine104is offset along the y-axis relative to the bolt106, the topmost cartridge may also be offset relative to the centerline of magazine104as the centerlines of magazine104and bolt106coincide when viewed from above. In other words, the y-coordinate of the centerline of the topmost cartridge112inFIG.12may be different from the y-coordinate of the centerline of the magazine104(especially its upper bulge), as well as the y-coordinate of the centerline of the bolt106. As noted above, since the centerline of the magazine104and the centerline of the bolt106may coincide when viewed from above, they may also share the same y-coordinate.

FIG.13Aillustrates a rear section view of a magazine assembly1304and a bolt1302in the prior art Magazine assembly1304further illustrates an optional mag stop1335-a.FIG.13Billustrates a rear section view of a magazine assembly1314, a bolt1312, and an optional mag stop1335-bin accordance with one or more implementations. In some cases,FIG.13Bmay implement one or more aspects of the figures described herein, including at leastFIGS.1,4, and10. As shown, the magazine assembly1304inFIG.13A(prior art) may comprise a centerline1308(also referred to as a center plane), which may coincide with the centerline of a topmost cartridge1306and the centerline of the bolt1302. Contrastingly, the narrow lower portion of the magazine assembly1314inFIG.13Bmay comprise a first centerline1318, which may coincide with the centerline of the topmost cartridge1316. Further, the upper bulged portion of the magazine assembly1314may comprise a second centerline1320, which may be different from the first centerline1318. In some cases, the centerline of the upper bulged portion may coincide with a centerline of the bolt1312, a centerline of the magazine well (not shown), and/or a longitudinal axis passing through the barrel of the firearm (not shown).

In some cases, this centerline offset along with positioning the topmost cartridge1316higher up in the firearm (i.e., with respect to the vertical position of the topmost cartridge1306in the prior art) may enable a greater area of overlap between the bolt1312and the topmost cartridge1316, thereby reducing the chances of the bolt failing to extract the topmost cartridge1316. For instance, as illustrated inFIGS.13A and13B, a plane1324tangential to a bottom surface of the topmost cartridge1306may be lower (i.e., with respect to the distal end of the housing) than a plane1322tangential to a bottom surface of the topmost cartridge1316. In other words, the topmost cartridge1312inFIG.13Bmay be higher up in the firearm than the topmost cartridge1306in the prior art, which may serve to alleviate bolt face overlap issues by maximizing bolt face engagement.

In some cases, magazines may comprise one or more mag stops (e.g., mag stop1335-a, mag stop1335-b) configured to contact a downward-facing surface or edge of the magazine well. These mag stops may establish a height that a magazine is set into the magazine well. According to aspects of the current disclosure, mag stop1335-bmay be positioned lower on the magazine1314(i.e., with respect to a top of its feedlips), as compared to the position of the mag stop1335-aon magazine1304(i.e., with respect to a top of its feedlips). In this way, the mag stop1335-bin magazine1314may be positioned further away, in a vertical direction, from a top of its feedlips, as compared to the prior-art magazine. In some aspects, positioning the mag stop1335-blower on the magazine1314may also allow the magazine1314to be inserted higher up within the magazine well of the firearm, as compared to a typical magazine. Accordingly, and as illustrated, the topmost cartridge1316may also be positioned higher up in the firearm, which may allow for a greater degree of overlap between the bolt1312and the topmost cartridge1316.

As previously described, the magazine1314according to the present disclosure may also comprise asymmetrical feedlips (e.g., feedlips114-aand114-binFIG.11), where the feedlips are positioned at different heights with respect to the proximal end of the housing. It should be noted that, the feedlips may be shaped and positioned above the upper bulged portion105. In contrast, the feedlips of magazine1304inFIG.13Amay be positioned at the same height with respect to the bottom or proximal end of the housing, as shown by a plane1310tangential to the top surface of the feedlips.

FIG.14illustrates a rear view of a magazine assembly1404and a bolt1402according to an alternate embodiment of the disclosure.FIG.14may implement one or more aspects of the figures described herein, including at leastFIGS.1,4, and/or10.

As shown, a centerline1406of the narrow lower end of the magazine assembly1404may not coincide with a centerline1408of the bolt1402. In some cases, the centerline1406of the narrow lower end may or may not coincide with a centerline of the topmost cartridge (not shown) on the follower. In some cases, the centerline1408of the bolt may also be off-set or misaligned with respect to the centerline of the topmost cartridge. Further, the centerline1408of the bolt may or may not coincide with the upper bulged portion of the magazine assembly1404. Additionally or alternatively, the centerline of the upper bulged portion may be misaligned with respect to the centerline1406of the narrow lower portion. In yet other cases, the centerline of the upper bulged portion and the narrow lower portion (i.e., a centerline of the magazine assembly1404) may coincide with a centerline of the topmost cartridge, where this common centerline (e.g., centerline1406) may be off-set from the centerline1408of the bolt1402. In some aspects, the various configurations discussed in relation toFIG.14and the other figures described herein may serve to optimize cartridge feeding by forcing the topmost cartridge in the magazine to be slightly off-set from the bolt1402, thus alleviating bolt face overlap issues.

FIG.15illustrates a method1500for manufacturing a firearm magazine in accordance with one or more implementations. In some examples, method1500may implement one or more aspects of the figures described herein. In some cases, the firearm magazine described in relation toFIG.15may be configured to store and feed cartridges of a first size into a firearm originally configured to fire cartridges of a second larger size. The firearm may comprise one of a bolt or a slide movable between an open and a closed position, where the bolt or the slide may be adapted to load cartridges from the magazine into a chamber of the firearm.

At1502, the method1500may comprise forming an asymmetrical elongated housing with a proximal end, a distal end, and at least one sidewall. In some examples, the method1500may optionally comprise forming at least one tapered section between the proximal and distal end.

At1504, the method1500may comprise affixing a first plate, such as a floor plate, at the proximal end. Further, at1506, the method may comprise positioning a follower in the asymmetrical elongated housing. In some embodiments, the follower may be configured to support a plurality of cartridges.

At1508, the method1500may comprise positioning a spring between the follower and the first plate, wherein the spring is configured to move or slide the follower within the housing based on a compression or decompression of the spring.

At1510, the method1500may comprise forming feedlips at the distal end of the elongated housing, wherein the feed lips are adapted to hold a topmost cartridge of a plurality of cartridges within the firearm magazine until the topmost cartridge is fed into a chamber of the firearm upon action of the bolt or the slide of the firearm, and wherein one or more of the feedlips, the elongated housing, and the tapered section are shaped to force the topmost cartridge to be off-center from the bolt of the firearm so as to increase an engagement or overlap between the bolt and the topmost cartridge prior to feeding. In some cases, the topmost cartridge may be in a single stack configuration, although different cartridge configurations are contemplated in other embodiments.

As used herein, the recitation of “at least one of A, B and C” is intended to mean “either A, B, C or any combination of A, B and C.” The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

The terms and expressions employed herein are used as terms and expressions of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof. Each of the various elements disclosed herein may be achieved in a variety of manners. This disclosure should be understood to encompass each such variation, be it a variation of an embodiment of any apparatus embodiment, a method or process embodiment, or even merely a variation of any element of these. Particularly, it should be understood that the words for each element may be expressed by equivalent apparatus terms or method terms—even if only the function or result is the same. Such equivalent, broader, or even more generic terms should be considered to be encompassed in the description of each element or action. Such terms can be substituted where desired to make explicit the implicitly broad coverage to which this invention is entitled.

As but one example, it should be understood that all action may be expressed as a means for taking that action or as an element which causes that action. Similarly, each physical element disclosed should be understood to encompass a disclosure of the action which that physical element facilitates. Regarding this last aspect, by way of example only, the disclosure of a “protrusion” should be understood to encompass disclosure of the act of “protruding”—whether explicitly discussed or not—and, conversely, were there only disclosure of the act of “protruding”, such a disclosure should be understood to encompass disclosure of a “protrusion”. Such changes and alternative terms are to be understood to be explicitly included in the description.