COMPACT ANTI-TILT FOLLOWER FOR AN AMMUNITION MAGAZINE
A follower for a firearm magazine is disclosed. In one embodiment, the follower has a top platform, a proximal end, a distal end, and at least one slider rail. The top platform is shaped to seat a cartridge and has a cartridge case shoulder region, a cartridge case head region, and a distal region. The proximal end has a first surface shaped to engage a proximal interior region of a firearm magazine housing. The distal end has a second surface shaped to engage a distal interior region of the firearm magazine housing. The slider rail is on a side of the follower and extends down from the top platform at a position that is between and remote from both the proximal end of the follower and the distal end of the follower. The follower does not have a slider rail extending from or adjacent to the second surface of the follower.
This application claims priority to U.S. Provisional Application No. 62/007,270 filed Jun. 3, 2014 and entitled “COMPACT ANTI-TILT FOLLOWER FOR AN AMMUNITION MAGAZINE,” the entire disclosure of which is hereby incorporated by reference for all purposes, as if fully set forth herein.
COPYRIGHTA portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent disclosure, as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all rights available and provided by copyright law.
FIELD OF THE INVENTIONThe present invention relates to the field of firearms. In particular, but not by way of limitation, the present invention relates to an improved follower and casing for an ammunition magazine.
BACKGROUND OF THE INVENTIONFirearm magazines are regularly used with firearms to allow for convenient storage and feeding of multiple cartridges to a firearm. Traditional magazines generally have a spring-loaded follower for guiding cartridges through the magazine housing to the top or mouth of the magazine where a firearm bolt can push one cartridge at a time into a chamber of the firearm. Although traditional magazines are generally functional, many types may be prone to jamming, can be unreliable, or are otherwise unsatisfactory. Moreover, it is desirable to provide for smaller or more compact followers and/or smaller magazine housings. Accordingly, a system and method are needed to address the shortfalls of present technology and to provide other new and innovative features.
SUMMARYExemplary aspects of the present disclosure that are shown in the drawings are summarized below. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment or aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments or aspects.
In one example, the follower has a top platform, a proximal end, a distal end, and at least one slider rail. The top platform is shaped to seat a cartridge and has a cartridge case shoulder region, a cartridge case head region, and a distal region. The proximal end has a first surface shaped to engage a proximal interior region of a firearm magazine housing. The distal end has a second surface shaped to engage a distal interior region of the firearm magazine housing. The slider rail is on a side of the follower and extends down from the top platform at a position that is between and remote from both the proximal end of the follower and the distal end of the follower. The follower does not have a slider rail extending from or adjacent to the second surface of the follower.
In another example, a magazine assembly for storing and feeding cartridges to a chamber of a firearm is provided. The magazine assembly has a housing, a follower, and a spring. The housing has a distal side and at least one curved bearing rail on an inside surface of the housing. The follower has a top platform shaped to seat a cartridge, the top platform including a cartridge case shoulder region shaped to abut at least a distal region of a cartridge case of the cartridge, a cartridge case head region shaped to abut a case head of the cartridge, and a distal region associated with a tip of the cartridge. The follower also has a proximal end including a first surface shaped to engage a proximal interior region of the housing, a distal end including a second surface shaped to engage a distal interior region of the housing; and at least one slider rail. The at least one slider rail is on a side of the follower, extending from the top platform at a position that is remote from both the proximal end of the follower and the distal end of the follower. The at least one slider rail is shaped to engage the at least one curved bearing rail of the housing. The follower spring is between the follower and a floor of the housing to apply a biasing force on the follower. The follower does not have a slider rail extending from or adjacent to the second surface of the follower.
In another example, a follower is provided, having a top platform, a proximal end, a distal end, a first elongated protrusion, and a second elongated protrusion. The top platform is shaped to seat a cartridge and has a distal region, a case shoulder region, and a case head region. The distal end has a tapered tip. The first elongated protrusion is on a first side of the follower and has a curved longitudinal axis shaped to slidably engage a first curved recess in a first side of the housing. The second elongated protrusion is on a second side of the follower and has a curved longitudinal axis shaped to slidably engage a second curved recess in a second side of the housing. The first elongated protrusion and the second elongated protrusion are positioned on opposing sides of the follower. The first elongated protrusion and the second elongated protrusion are more proximal to the case shoulder region of the top platform than to the case head region of the top platform.
These and other examples and aspects are more fully described in the Detailed Description section. It is to be understood, however, that there is no intention to limit the invention to the forms described in this Summary or in the Detailed Description. One skilled in the art can recognize that there are numerous modifications, equivalents and alternative constructions that fall within the spirit and scope of the invention as expressed in the claims.
Various objects and advantages and a more complete understanding of the present invention are apparent and more readily appreciated by reference to the following Detailed Description and to the appended claims when taken in conjunction with the accompanying Drawings wherein:
As discussed above, in one exemplary embodiment the present disclosure describes a compact anti-tilt follower for a firearm magazine as will be described below. The follower can be produced in a more compact fashion (e.g., having a shorter overall height) by using a substantially vertical slider rail along one or more sides of the follower having a greater aspect ratio (length over width) than prior art anti-tilt features. The greater aspect ratio enables more anti-tilt effect from the slider than prior-art designs and thereby enables a shorter follower with the same or better anti-tilt abilities than prior art designs. Advantages of a more compact follower are less friction with an inside of a magazine housing and a magazine that can potentially house more cartridges. In another exemplary embodiment, this disclosure describes a housing for a firearm magazine, which will be described in further detail below. In a third exemplary embodiment, the disclosure describes a magazine assembly having a compact anti-tilt follower and a firearm magazine housing as described below.
Referring now to the drawings, where like or similar elements are designated with identical reference numerals throughout the several views,
Referring now to
Continuing with
The housing 102 may also be curved, as shown in the figures, to provide for smooth feeding of the cartridges; however, it should be understood by those skilled in the art that the housing 102 may be straight in some embodiments. That is, for the purposes of this disclosure, the term “curvature” may in some embodiments be used to describe a feature having a curvature of infinite radius that is straight, a planer radius, a spherical radius, a spiral, a helix or any combination of the preceding. Moreover, the housing 102 may be configured to hold relatively few rounds, or up to a hundred rounds or more, with thirty rounds being a standard capacity in some embodiments. The top end 106 of the housing 102 may be interchangeable with other types of magazine housings.
Referring now to
In
The second side of the housing 102 may also have a bearing 112 on the inside wall thereof (not visible in
Referring now to
The slider 120 is configured to control the tilt of the follower 104 as the follower 104 moves within the housing 102. In the illustrated embodiment, the slider 120 has a curvature that may mimic a curvature of an inside of the housing 102 (e.g., a constant internal curvature). In some embodiments, however, the follower 104, and axis B, may not be curved at all, or not have the same curvature, even where the bearing 112 is curved, so long as the tolerances are chosen to allow the follower 104 to smoothly pass through the housing 102. For example, a slider 120 may have an infinite curvature (that is, straight), yet still be used in a curved housing 102. In this straight slider 120 embodiment, the curvature of the slider 120 does not mimic the curvature of the inside of the housing 102. Like with the housing 102, the slider 120 may follow a path that is straight, a planer radius, a spherical radius, a spiral, a helix or any combination of the preceding. Furthermore, the slider 120 may be partially curved; that is, the 120 may follow axis B for a portion of the length of the slider 120, and follow a straight line for another portion of the length of the slider 120. The axis B may correspond to a curvature in the bearing 112, but it need not necessarily do so.
It will be understood by those skilled in the art and active in the firearms industry that the general term “tilt” may be used to describe the tilting about one or more of the pitch, roll, and yaw axes. In
As shown in
As depicted in
Continuing with
It should be understood by those skilled in the art that the terms “slider” and “bearing” are not intended to limit this disclosure to the protrusion and channel shown. Instead, it should be understood that the term “slider” is meant to indicate the moving component, i.e., the portion of the follower 104 that moves within the housing 102. Likewise, it should be understood that the term “bearing” is merely meant to indicate the stationary component, i.e., the portion of the housing 102 that guides the movement of the follower 104. It should be understood that the elements can be reversed while preserving the function, with the housing 102 having a protruding bearing and the follower 104 have a recessed slider. Likewise, where two sliders and two bearings are implemented, it should be understood that one slider may be protruding while the second is recessed.
As can be seen in
In
Referring briefly back to
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In
Locating the slider 120 near the center of gravity therefore provides more stability to the follower 104 when it is being guided through the housing 102, as compared to the prior art. Due to the geometry most often required for both the cartridge and the magazine interface, the most practical location is often is near to the cartridge shoulder in the housing 102. This location also allows for a reduction in the size required from the top of the follower 126 to the bottom 127 of the follower 104. In turn, the follower 104 is more compact than prior art followers, and, where the spring geometry allows, a particularly compact housing 102 may be constructed for use with the compact follower 104 described herein.
The slider 120 may be on a side of the follower 104, and a second slider 120 may be on an opposing side of the follower 104. Although depicted as extending along the entire length of the side of the follower 104, it should be understood that the slider 120 need not necessarily extend along the entire length of the side. All that is necessary is that the slider 120 extend far enough so as to ensure that tilt is controlled to an acceptable tolerance when the follower 104 is traveling through the housing 102 of the magazine 100. In some embodiments, the slider 120 can have a profile, when viewed from above, resembling at least a portion of a rectangle, square, circle, pill-shape, multi-faceted shape, and many others. Moreover, the slider 120 may be interrupted at one or more portions between the top 126 and the bottom 127 of the follower (e.g., an “interrupted slider”). An interrupted slider may also exhibit various profile features or projections 390 when viewed from the side, as seen in
As can further be seen in
Similarly,
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The embodiment shown in
As can be seen in
Although the figures depict a follower 104 having a mirror-image slider 120 on both sides of the follower 104, it should be understood that this disclosure encompasses embodiments in which the follower 104 has only one slider 120, or in which two or more sliders 120 are not mirror images. As a non-limiting example, one slider 120 may have a square profile, while the other may have a round profile and/or be offset from the first slider 120. As another example, a first slider 720 may be configured to control most of the tilt requirements having looser tolerances, while a second slider 120 may be configured to engage only where tighter tolerances are required. That is, for example, a first slider 120 might control overall length of travel, while a second slider 120 may be configured to engage only where the follower 104 begins to tilt too far out of a desired tilt range. Such variations may provide advantages in manufacturing, such as loosening manufacturing tolerances for some components of the slider 104 or housing 102 while still maintaining strict control over the movement of the follower 104, and thus the overall reliability of the magazine assembly 100 itself.
Although the figures depict followers 104, 604, 704 having a top platform 126 that is flat, it should be understood that this disclosure encompasses the use of any top platform profile suitable for the intended use of feeding cartridges to a firearm chamber. As just a few examples, this disclosure contemplates a follower 104 having a rounded top platform, either concave or convex, as well as embodiments in which the top platform includes a ramp for shifting forces exerted on a cartridge, and top platforms having an angle to minimize contact area. Some top platforms encompassed by this disclosure are discussed in commonly-assigned U.S. Pat. No. 8,166,692 issued May 1, 2012, the contents of which are incorporated by reference herein in their entirety; however, it should be understood that other top platform profiles are encompassed.
It should also be understood that the compact anti-tilt follower 104 and housing 102 of any of the preceding embodiments can be adapted for use with ammunition of a variety of calibers, as well as a variety of firearm classes that use magazines for feeding multiple rounds to the firearm.
In conclusion, the present invention provides, among other things, a compact anti-tilt follower for guiding cartridges towards an exit of a housing of a firearm magazine. The invention may include a housing for a firearm magazine configured to guide an anti-tilt follower through the housing, and it may include an assembly having a compact anti-tilt follower and housing. Those skilled in the art can readily recognize that numerous variations and substitutions may be made in the invention, its use, and its configuration to achieve substantially the same results as achieved by the embodiments described herein. Accordingly, there is no intention to limit the invention to the disclosed exemplary forms. Many variations, modifications and alternative constructions fall within the scope and spirit of the disclosed invention as expressed in the claims.
Claims
1. A follower for a firearm magazine, the follower comprising:
- a top platform shaped to seat a cartridge, the top platform including a cartridge case shoulder region shaped to abut at least a distal region of a cartridge case of the cartridge, a cartridge case head region shaped to abut a case head of the cartridge, and a distal region associated with a tip of the cartridge;
- a proximal end including a first surface shaped to engage a proximal interior region of a firearm magazine housing;
- a distal end including a second surface shaped to engage a distal interior region of the firearm magazine housing; and
- at least one slider rail on a side of the follower; wherein
- the at least one slider rail extends down from the top platform at a position that is between and remote from both the proximal end of the follower and the distal end of the follower; and
- the follower does not have a slider rail extending from or adjacent to the second surface of the follower.
2. The follower of claim 1, wherein:
- the at least one slider rail is located closer to a center of gravity of the follower than to the distal end of the follower.
3. The follower of claim 2, wherein:
- the at least one slider rail is located distal of the center of gravity of the follower.
4. The follower of claim 1, wherein:
- the at least one slider rail is located distal of a center of gravity of the follower.
5. The follower of claim 1, wherein:
- the at least one slider rail extends below the top platform at least a portion of a length of the side of the follower; and
- the at least one slider rail has a curvature shaped to guide the follower along a curvature of a bearing rail in the firearm magazine housing.
6. The follower of claim 5, wherein:
- the second surface has a curvature shaped to conform to a curvature of the distal interior region of the firearm magazine housing.
7. The follower of claim 6, wherein:
- the curvature of the at least one slider rail is not identical to the curvature of the second surface.
8. The follower of claim 1, wherein:
- the distal region of the top platform is tapered between the cartridge case shoulder region and the distal end of the follower, such that the cartridge case shoulder region is wider than the distal end of the follower.
9. The follower of claim 1, comprising:
- a plurality of slider rails, wherein the at least one slider rail opposes a second one of the plurality of slider rails.
10. The follower of claim 1, comprising:
- a plurality of slider rails on the side of the follower.
11. The follower of claim 1, wherein:
- the slider rail has a longitudinal length and a width, the length at least 1.5 times the width.
12. The follower of claim 11, wherein:
- the length is at least 5 times the width.
13. The follower of claim 12, wherein:
- the length is at least 10 times the width.
14. The follower of claim 13, wherein:
- the length is at least 15 times the width.
15. The follower of claim 1, wherein:
- the at least one slider rail comprises a protrusion on the side of the follower or a recess in the side of the follower.
16. A magazine assembly for storing and feeding cartridges to a chamber of a firearm, the magazine assembly comprising:
- a housing having a distal side and at least one curved bearing rail on an inside surface of the housing;
- a follower having a top platform shaped to seat a cartridge, the top platform including a cartridge case shoulder region shaped to abut at least a distal region of a cartridge case of the cartridge, a cartridge case head region shaped to abut a case head of the cartridge, and a distal region associated with a tip of the cartridge, the follower further comprising: a proximal end including a first surface shaped to engage a proximal interior region of the housing; a distal end including a second surface shaped to engage a distal interior region of the housing; and at least one slider rail on a side of the follower; extending from the top platform at a position that is remote from both the proximal end of the follower and the distal end of the follower, the at least one slider rail shaped to engage the at least one curved bearing rail of the housing; wherein the follower does not have a slider rail extending from or adjacent to the second surface of the follower; and
- a follower spring between the follower and a floor of the housing to apply a biasing force on the follower.
17. The magazine assembly of claim 16, wherein:
- the housing comprises a longitudinal axis;
- the biasing force comprises a longitudinal component associated with the longitudinal axis; and
- the at least one slider rail and the at least one bearing rail are shaped and positioned to maximize the longitudinal component of the biasing force at a center of gravity of a cartridge placed in the magazine assembly.
18. A follower for a firearm magazine, the follower comprising:
- a top platform shaped to seat a cartridge, the top platform having a distal region, a case shoulder region, and a case head region;
- a proximal end;
- a distal end having a tapered tip; and
- a first elongated protrusion on a first side of the follower, the first elongated protrusion having a curved longitudinal axis shaped to slidably engage a first curved recess in a first side of the housing;
- a second elongated protrusion on a second side of the follower, the second elongated protrusion having a curved longitudinal axis shaped to slidably engage a second curved recess in a second side of the housing; wherein
- the first elongated protrusion and the second elongated protrusion are positioned on opposing sides of the follower; and
- the first elongated protrusion and the second elongated protrusion are more proximal to the case shoulder region of the top platform than to the case head region of the top platform.
19. The follower of claim 18, wherein:
- the first elongated protrusion and the second elongated protrusion are positioned closer to a center of gravity of the follower than to the proximal end of the follower; and
- the first elongated protrusion and the second elongated protrusion are positioned closer to the center of gravity of the follower than to the distal end of the follower.
20. The follower of claim 18, wherein:
- the first elongated protrusion has a longitudinal first length and a first width, the first width measured from a proximal side of the first elongated protrusion to a distal side of the first elongated protrusion, the first length being at least 10 times the first width;
- the second elongated protrusion has a longitudinal second length and a second width, the second width measured from a proximal side of the second elongated protrusion to a distal side of the second elongated protrusion, the second length at least 10 times the second width.
Type: Application
Filed: Jun 3, 2015
Publication Date: Dec 3, 2015
Inventors: Brian L. Nakayama (Arvada, CO), Nicholas Kielsmeier (Denver, CO), Eric Nakayama (Broomfield, CO), Eric Burt (Broomfield, CO)
Application Number: 14/730,141