FEED STOP FOR AMMUNITION MAGAZINE

Abstract

An ammunition magazine for a gun includes a magazine body defining an interior space in which a plurality of cartridges is receivable, a follower in the interior space configured to bias the cartridges toward an upper end of the magazine body, a feed lip at the upper end of the magazine body configured to engage a topmost cartridge received in the interior space, and a movable feed stop on the magazine body configured to press the topmost cartridge against the feed lip and thereby prevent the plurality of cartridges from being pushed out of the top of the magazine by the follower.

Claims

1. An ammunition magazine for a gun, comprising: a magazine body defining an interior space in which a plurality of cartridges is receivable; a follower in the interior space configured to bias the cartridges toward an upper end of the magazine body; a feed lip at the upper end of the magazine body configured to engage a topmost cartridge received in the interior space; and a movable feed stop on the magazine body configured to press the topmost cartridge against the feed lip.

2. The ammunition magazine of claim 1, wherein the feed stop is movable between: an extended position wherein the feed stop engages the topmost cartridge to press the topmost cartridge against the feed lip, and a depressed position wherein the feed stop does not engage the topmost cartridge.

3. The ammunition magazine of claim 2, wherein the feed stop is biased toward the extended position.

4. The ammunition magazine of claim 1, wherein the feed stop is configured to hold the topmost cartridge against the feed lip until an advancing bolt of the gun pushes the topmost cartridge toward a firing chamber of the gun.

5. The ammunition magazine of claim 1, wherein the feed stop exerts a pressing force on the topmost cartridge that is less than a pushing force exerted on the cartridge by an advancing bolt of the gun during cycling of the gun such that the topmost cartridge can be pushed out of contact with the feed lip and into a firing chamber of the gun by the bolt.

6. The ammunition magazine of claim 4, wherein the bolt is larger than a diameter of the topmost cartridge.

7. The ammunition magazine of claim 1, wherein the feed stop is on a side interior surface of the upper end of the magazine body spaced from the feed lip.

8. The ammunition magazine of claim 1, wherein the feed stop is on a side of the magazine opposite the feed lip.

9. The ammunition magazine of claim 1, wherein: the upper end of the magazine body includes first and second opposing sidewalls; the feed lip is at an upper end of the first sidewall; and the feed stop is pivotably connected to the second sidewall.

10. The ammunition magazine of claim 9, wherein the feed stop is spring biased toward an extended position wherein the feed stop engages the topmost cartridge to press the topmost cartridge against the feed lip.

11. The ammunition magazine of claim 9, wherein the feed lip is spaced from the second sidewall by a distance greater than a diameter of the topmost cartridge.

12. The ammunition magazine of claim 11, wherein the plurality of cartridges is receivable in the interior space in a single stack orientation.

13. The ammunition magazine of claim 1, wherein: the upper end of the magazine body includes first and second opposing sidewalls, a rear wall extending between the first and second opposing sidewalls, and a gap in the rear wall through which an advancing bolt of the gun can pass during cycling of the gun; and the gap has a width that is greater than a diameter of the topmost cartridge.

14. The ammunition magazine of claim 1, wherein: the feed stop is pivotably mounted to the magazine body; the feed stop is biased upwardly toward engagement with the topmost cartridge; and the feed stop is configured to pivot downwardly out of engagement with the topmost cartridge as an advancing bolt of the gun pushes the topmost cartridge toward a firing chamber of the gun.

15. The ammunition magazine of claim 13, wherein the feed stop is configured to pivot downwardly out of engagement with the topmost cartridge in response to the bolt or a bolt carrier contacting the feed stop and pushing the feed stop downwardly as the bolt pushes the topmost cartridge longitudinally forward toward the firing chamber.

16. The ammunition magazine of claim 1, wherein: the upper end of the magazine body includes first and second opposing sidewalls; the feed lip is at an upper end of the first sidewall; the feed stop is pivotably connected to the second sidewall; the feed stop is biased upwardly toward engagement with the topmost cartridge; the second sidewall includes a guide slot in which a portion of the feed stop is slidably receivable; and the feed stop is configured to pivot down into the guide slot and disengage the topmost cartridge as an advancing bolt of the gun pushes the topmost cartridge toward a firing chamber of the gun.

17. The ammunition magazine of claim 1, wherein: the magazine is a drum magazine comprising a drum portion and a feed tower portion; and the plurality of cartridges is receivable in the interior space in a single stack orientation.

18. An ammunition magazine for a gun, comprising: a magazine body defining an interior space in which a plurality of cartridges is receivable; a follower in the interior space configured to bias the cartridges toward an upper end of the magazine body; a feed lip at the upper end of the magazine body configured to engage a topmost cartridge received in the interior space; and a feed stop on a sidewall of the magazine body opposite the feed lip configured to hold the topmost cartridge against the feed lip until an advancing bolt of the gun pushes the topmost cartridge toward a firing chamber of the gun.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0015] Non-limiting and non-exhaustive embodiments are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various drawings unless otherwise specified. In the drawings, not all reference numbers are included in each drawing, for the sake of clarity.

[0016] FIG. 1 is a fragmentary rear view of the upper end of a prior art double stack box magazine for a firearm containing a plurality of cartridges with an exemplar bolt carrier group positioned against a rear end of the topmost cartridge in the magazine ready to push the topmost cartridge toward a firing chamber of the firearm. The bolt carrier group is shown sectioned for clarity.

[0017] FIG. 2 is a fragmentary front view of the upper end of the prior art double stack box magazine of FIG. 1.

[0018] FIG. 3 is an elevated left side perspective view of a firearm having a receiver with a magazine well in which an embodiment of a novel ammunition magazine constructed in accordance with the present invention is received. The magazine is depicted fully loaded with tapered .50 caliber cartridges..

[0019] FIG. 4 is an elevated front left perspective view of the magazine of FIG. 3 with the cartridges omitted for clarity and an embodiment of a novel feed stop constructed in accordance with the present invention shown in an extended position on the right feed tower sidewall at the upper end of the magazine.

[0020] FIG. 5 is a magnified detail view of the objects of FIG. 4 at location A with the feed lip omitted for clarity.

[0021] FIG. 6 depicts the objects of FIG. 5 with the novel feed stop shown in a depressed position.

[0022] FIG. 7 is an elevated rear left perspective view of the objects of FIG. 6 with the left feed tower sidewall omitted for clarity.

[0023] FIG. 8 is a magnified sectional view of the objects of FIG. 7 at location B taken along line 8-8.

[0024] FIG. 9 is a fragmentary perspective sectional view taken along line 9-9 of FIG. 8.

[0025] FIG. 10 is an elevated left side exploded perspective view of the objects of FIG. 8.

[0026] FIG. 11 is a depressed right side perspective view of the feed stop of FIG. 6.

[0027] FIG. 12 is an elevated front right perspective view of the objects of FIG. 6 with the feed lip present for clarity.

[0028] FIG. 13 is a rear elevational view of the ammunition magazine of FIG. 3 showing the ammunition cartridges in a single stack orientation and the feed stop in the extended position holding the topmost cartridge against the feed lip. The rear wall of the feed tower is transparent for clarity.

[0029] FIG. 14 is a fragmentary front perspective detail view of the upper end of the ammunition magazine of FIG. 13.

[0030] FIG. 15 is a rear elevational view of the objects of FIG. 14 showing the exemplar bolt carrier group of FIG. 1 positioned against the rear end of the topmost cartridge ready to push the topmost cartridge toward a firing chamber of the firearm.

[0031] FIG. 16 is a right side elevational view of the magazine of FIG. 3 showing the feed stop in the extended position holding the topmost cartridge against the feed lip on the left feed tower sidewall and the exemplar bolt carrier group of FIG. 1 positioned against the rear end of the topmost cartridge ready to push the topmost cartridge toward a firing chamber of the firearm. The right feed tower sidewall is omitted for clarity.

[0032] FIG. 17 is a right side view of the objects of FIG. 16 showing the bolt carrier moving the feed stop downward out of the extended position and toward the depressed position as the bolt carrier advances the bolt to push the topmost cartridge into the firing chamber.

[0033] FIG. 18 is a right side view of the objects of FIG. 16 showing the bolt carrier holding the feed stop down in the depressed position with the topmost cartridge fully chambered.

DETAILED DESCRIPTION

[0034] The details of one or more embodiments of the present invention are set forth in this document. Modifications to embodiments described in this document, and other embodiments, will be evident to those of ordinary skill in the art after a study of the information provided herein. The information provided in this document, and particularly the specific details of the described exemplary embodiment(s), is provided primarily for clearness of understanding and no unnecessary limitations are to be understood therefrom. In case of conflict, the specification of this document, including definitions, will control.

[0035] While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts that are embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the invention. Those of ordinary skill in the art will recognize numerous equivalents to the specific apparatus and methods described herein. Such equivalents are considered to be within the scope of this invention and are covered by the claims.

[0036] While the terms used herein are believed to be well understood by one of ordinary skill in the art, a number of terms are defined below to facilitate the understanding of the embodiments described herein. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the subject matter disclosed herein belongs. The terms defined herein have meanings as commonly understood by a person of ordinary skill in the areas relevant to the present invention. Terms such as a, an, and the are not intended to refer to only a singular entity, but rather include the general class of which a specific example may be used for illustration. The terminology herein is used to describe specific embodiments of the invention, but their usage does not delimit the invention, except as set forth in the claims.

[0037] As described herein, an upright position is considered to be the position of apparatus components while in proper operation or in a natural resting position as described and shown herein, for example, in FIG. 3. The upright firing position of a firearm is a generally level firing position. Vertical, horizontal, above, below, side, top, bottom, upper, lower, and other orientation terms are described with respect to this upright position during operation, unless otherwise specified, and are used to provide an orientation of embodiments of the invention to allow for proper description of example embodiments. A person of skill in the art will recognize, however, that the apparatus can assume different orientations when in use.

[0038] As used herein, the terms front and forward means in a direction extending toward the muzzle of the firearm. In some cases, the term forward can also mean forward beyond the muzzle of the firearm. The terms aft and rear means in a direction extending away from the muzzle of the firearm toward a rear end of a firearm. In some cases, the term rearward can also mean rearward beyond the rear end of the firearm.

[0039] As used herein, the term gun means a weapon incorporating a tube from which one or more projectiles are propelled by an explosive force or a compressed gas. For the avoidance of doubt, the term gun includes firearms, airguns, grenade launchers, cannons, and the like.

[0040] As used herein, the term cartridge means a preassembled ammunition packaging one or more projectiles within a case that is made to fit within a firing chamber of a breechloading gun barrel. A cartridge can also include a propellant substance and an ignition device packaged within the case. In some embodiments, a cartridge can be a monolithic projectile for an airgun.

[0041] The term when is used to specify orientation for relative positions of components, not as a temporal limitation of the claims or apparatus described and claimed herein unless otherwise specified.

[0042] The terms above, below, over, and under mean having an elevation or vertical height greater or lesser than and are not intended to imply that one object or component is directly over or under another object or component.

[0043] The phrase in one embodiment, as used herein does not necessarily refer to the same embodiment, although it may. Conditional language used herein, such as, among others, can, might, may, e.g., and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or states. Thus, such conditional language is not generally intended to imply that features, elements and/or states are in any way required for one or more embodiments.

[0044] All measurements should be understood as being modified by the term about regardless of whether the word about precedes a given measurement.

[0045] The terms significantly, substantially, approximately, about, relatively, or other such similar terms that may be used throughout this disclosure, including the claims, are used to describe and account for small fluctuations, such as due to variations in manufacturing or processing from a reference or parameter. Such small fluctuations include a zero fluctuation from the reference or parameter as well. For example, they can refer to less than or equal to 10%, such as less than or equal to 5%, such as less than or equal to 2%, such as less than or equal to 1%, such as less than or equal to 0.5%, such as less than or equal to 0.2%, such as less than or equal to 0.1%, such as less than or equal to 0.05%. In the absence of a reference parameter from the context surrounding its use, the term substantially as used herein means what is considered normal or possible within the limits of applicable industry-accepted manufacturing practices and tolerances.

[0046] All references to singular characteristics or limitations of the present disclosure shall include the corresponding plural characteristic(s) or limitation(s) and vice versa, unless otherwise specified or clearly implied to the contrary by the context in which the reference is made.

[0047] All combinations of method or process steps as used herein can be performed in any order, unless otherwise specified or clearly implied to the contrary by the context in which the referenced combination is made.

[0048] The methods and devices disclosed herein, including components thereof, can comprise, consist of, or consist essentially of the essential elements and limitations of the embodiments described herein, as well as any additional or optional components or limitations described herein or otherwise useful.

[0049] Referring now generally to FIGS. 3-18, there is depicted a magazine 10 for a firearm 100 equipped with an embodiment of a novel feed stop 50 constructed in accordance with the present invention. In the depicted embodiment, the magazine 10 is exemplified as a drum type magazine. However, it is to be understood that the novel feed stop 50 disclosed herein is compatible with other types of magazines, including but not limited to detachable box type magazines. As such, no limitation should be implied on the type or configuration of magazine with which the novel feed stop 50 is compatible unless specifically set forth in the appended claims.

[0050] The magazine 10 includes a magazine body 12 designed to contain a plurality of cartridges 2. The magazine body 12 defines an interior space 15 in which the cartridges 2 are received in a single column or single stack orientation. A spring-loaded follower 14 received in the interior space 15 is arranged to push the cartridges 2 toward an upper end 16 of the magazine body 12. The magazine body 12 includes a cylindrical drum portion 18 and a linear feed tower portion 20. Cartridges 2 stored in the interior space 15 of the magazine 10 are advanced by the follower 14 around the drum 18 and up through the feed tower 20 to the upper end 16 of the magazine. The upper end 16 of the magazine body 12 toward which the follower 14 pushes the cartridges 2 is an upper end 16 of the feed tower 20. The feed tower 20 includes opposing left and right tower sidewalls 22, 24, a front wall 26, and a rear wall 28. The rear wall 28 defines a gap 30 through which a portion of an advancing bolt 106 and bolt carrier 108 of a firearm 100 can pass when moving a topmost cartridge 5 from the upper end 16 of the magazine into the firing chamber 102 of the firearm 100. The gap 30 has a width 33 that is greater than a diameter 3 of the cartridges 2. The width 33 of the gap 30 is also greater than a width 103 of the portion of the advancing bolt 106 and bolt carrier 108.

[0051] A single feed lip 40 is detachably connected to the upper end 16 of the left feed tower sidewall 22 via fasteners 32. The feed lip 40 defines a hollow space 42 underneath the uppermost tip of the feed lip 40 in which the topmost cartridge 5 is receivable. In this way, the feed lip 40 is shaped and sized to receive and engage the topmost cartridge 5 as the cartridges 2 are biased around and upward through the magazine 10 by the follower 14. When connected to the feed tower sidewall 22, the feed lip 40 forms part of the upper end 16 of the magazine 10.

[0052] The feed stop 50 is pivotably connected to a side interior surface 44 of the right feed tower sidewall 24 at the upper end 16 of the magazine body 12 opposite the feed lip 40. The feed stop 50 is received in a recess 46 formed in the right tower sidewall 24. The feed stop 50 is spaced from the left feed tower sidewall 22 and the feed lip 40. The feed stop 50 is arranged to press the topmost cartridge 5 against the feed lip 40 in a direction that is transverse to a longitudinal axis of the topmost cartridge 5. More specifically, the feed stop 50 is pivotable between an extended position (e.g., FIGS. 4-5, 13-16) and a depressed position (e.g., FIGS. 6-9, 18). In the depressed position, the feed stop 50 does not engage the topmost cartridge 5. In the extended position, the feed stop 50 engages the topmost cartridge 5 and exerts a pressing force against a side of the topmost cartridge 5 to press the topmost cartridge 5 in a side direction against the feed lip 40, as best shown in FIGS. 13-16. The feed stop 50 can be arranged on the feed tower sidewall 24 to press the topmost cartridge 5 upward, laterally away from the feed tower sidewall 24, or both.

[0053] The feed stop 50, alone or in combination with a pushing force transmitted from the follower 14 through each cartridge 2 to the topmost cartridge 5, holds the topmost cartridge 5 against the feed lip 40 either until the topmost cartridge 5 is manually removed from the magazine or the bolt carrier group 110 pushes the topmost cartridge 5 toward the firing chamber 102 of the gun barrel 104. Regardless of the direction in which the feed stop 50 presses the topmost cartridge 5, the feed stop 50 exerts a pressing force on the topmost cartridge 5 that is less than a longitudinal pushing force exerted on the cartridge 5 by the bolt carrier group 100 during cycling of the firearm 100 such that the topmost cartridge 5 can be pushed out of contact with the feed lip 40 and into a firing chamber 102 of the gun barrel 104 by the bolt carrier group 110. In this way, the feed stop 50 holds the topmost cartridge 5 against the feed lip 40 until the advancing bolt carrier group 110 pushes the topmost cartridge 5 toward the firing chamber 102 of the firearm 100. The feed stop 50 thus works in combination with the feed lip 40 to prevent the cartridges 2 from being pushed out of the upper end 16 of the magazine 10 by the follower 14, thereby overcoming the deficiencies of the prior art associated with single stack ammunition magazines for firearms with bolts 106 and bolt carriers 108 that are larger than cartridges the firearms are designed to fire.

[0054] As best shown in FIGS. 5 and 8, the feed stop 50 is biased toward the extended position by a spring 52. The spring 52 is seated in a blind socket 54 defined in a ledge 48 on the right tower sidewall 24 underneath the feed stop 50. A portion of the spring extends out of the blind socket 54 and into an overlying blind hole 56 defined in a bottom surface of the feed stop 50. The spring 52 is captured in the feed tower sidewall 24 between the ledge 48 and the feed stop 50.

[0055] Turning now to FIGS. 8-11, the feed stop 50 is pivotably connected to the right feed tower sidewall 24 by a first threaded fastener 58. An unthreaded spacer bushing 60 extends through a smooth counterbored hole 51 defined in the rear end 53 of the feed stop 50 and into a threaded counterbored hole 62 defined in the side interior surface 44 of the tower sidewall 24. The first threaded fastener 58 extends through the spacer bushing 60 and into the threaded counterbored hole 62 to pivotably secure the feed stop 50 to the sidewall 24. A head 59 of the first threaded fastener 58 can sit flush with or below a side surface 55 of the feed stop 50 so that the first threaded fastener 58 does not interfere with the feed and chambering of cartridges 2 through and from the magazine 10, respectively.

[0056] A second threaded fastener 64 extends through a threaded counterbored hole 57 defined in the feed stop 50. The threaded counterbored hole 57 is spaced longitudinally forward along the feed stop 50 from the smooth counterbored hole 51. An end of the second threaded fastener 64 extends out of the feed stop 50 through the threaded counterbored hole 57 and into an arcuate travel slot 65 defined in the side interior surface 44 of the tower sidewall 24. Contact between the end of the second threaded fastener 64 and the ends 66 of the travel slot 65 limits the range of pivotable movement of the feed stop 50. The length of the arcuate travel slot 65 can be varied to coordinately vary the relative height or depth of the extended and depressed positions of the feed stop 50, respectively, so as to modify the magazine 10 to accommodate cartridges 2 of different calibers and shapes. A head 68 of the second threaded fastener 64 can sit flush with or below the side surface 55 of the feed stop 50 so that the second threaded fastener 64 does not interfere with the feed and chambering of cartridges 2 through and from the magazine 10, respectively.

[0057] Returning now to FIGS. 5-9 and 11, the feed stop 50 includes a front end 70 with a protrusion in the form of a downwardly extending leg 72. The leg 72 at the front end 70 of the feed stop 50 is thinner than the remainder of the feed stop 50. The leg 72 is slidably received in a guide slot 75 defined in portion of the tower sidewall protruding from the side interior surface 44. The guide slot 75 guides the front end 70 of the feed stop 50 as the feed stop pivots between the extended and depressed positioned during cycling of the firearm 100 so as to constrain the movement of the feed stop 50 to a vertical plane.

[0058] Referring now to FIGS. 14-18, the feed stop 50 is shaped and sized so as to hold the topmost cartridge 5 in the magazine tangent to the feed lip 40 when the feed stop 50 is in the extended position. While held against the feed lip 40 by the feed stop 50, the topmost cartridge 5 sits in the hollow space 42 underneath the uppermost tip of the feed lip 40. This positions the topmost cartridge 5 horizontally so it can be readily stripped from the magazine 10 and pushed by the bolt 106 into the firing chamber 102 of the gun barrel 104. The feed stop 50 itself can have a slightly bent, non-linear shape. This ensures that the feed stop 50 pivots downward smoothly and easily when contacted by the bolt 106 or bolt carrier 108 as the bolt carrier 108 advances the bolt 106 to push the topmost cartridge 5 into the firing chamber 102 during cycling of the firearm 100.

[0059] More specifically, when viewed in the extended position, the feed stop 50 defines an upper surface 76 and at least one rear surface 78 pitched at a downward angle relative to the upper surface 76. This at least one rear surface 78 is angled so as to allow the bolt 106 and bolt carrier 108 to slide over the rear surface 78 and thereby push (i.e., pivot) the feed stop 50 downward away from and out of engagement with the topmost cartridge 5, and toward the depressed position as the advancing bolt carrier group 110 moves longitudinally forward and pushes the topmost cartridge 5 into the firing chamber 102. When the topmost cartridge 5 is fully chambered, as shown in FIG. 18, the feed stop 50 is held in the depressed position by the bolt carrier 108. When the bolt carrier group 110 retracts longitudinally rearward of the upper end 16 of the magazine body 10, the follower 14 pushes the next cartridge 2 into the position of topmost cartridge 5 while the spring 52 pushes the feed stop 50 back upward toward the extended position where the feed stop 50 will then hold the new topmost cartridge 5 against the feed lip 40 until the advancing bolt carrier group 110 chambers the cartridge 5 as previously described.

[0060] The above description is only a preferred and feasible embodiment of this application, and is not intended to limit the patentable scope of this application. Although embodiments of the present invention have been described in detail, it will be understood by those skilled in the art that various modifications can be made therein without departing from the spirit and scope of the invention as set forth in the appended claims. For example, in other embodiments, the feed stop can be on a left side of the upper end of the magazine body while the feed lip can be on the right side of the upper end of the magazine body.

[0061] This written description uses examples to disclose the invention and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

[0062] It will be understood that the particular embodiments described herein are shown by way of illustration and not as limitations of the invention. The principal features of this invention may be employed in various embodiments without departing from the scope of the invention. Those of ordinary skill in the art will recognize numerous equivalents to the specific apparatus and methods described herein. Such equivalents are considered to be within the scope of this invention and are covered by the claims.

[0063] All of the compositions and/or methods disclosed and claimed herein may be made and/or executed without undue experimentation in light of the present disclosure. While the compositions and methods of this invention have been described in terms of the embodiments included herein, it will be apparent to those of ordinary skill in the art that variations may be applied to the compositions and/or methods and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit, and scope of the invention. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope, and concept of the invention as defined by the appended claims.

[0064] Thus, although there have been described particular embodiments of the present invention, it is not intended that such references be construed as limitations upon the scope of this invention except as set forth in the following claims.