Abstract:
The present invention includes modifications to a standard magazine and magazine follower to effect automatic ejection of an ammunition magazine from a weapon, once the last round has left the magazine.

Description:
FIELD OF INVENTION 
       [0001]    The present invention is generally related to ammunition magazines for automatic or semi-automatic weapons. In particular, the present invention is directed to a modification in an ammunition magazine to facilitate automatic ejection. 
       BACKGROUND ART 
       [0002]    The purpose of modern automatic weapons, whether used in semi-automatic, or full automatic modes, is to provide fast, accurate placement of rounds downrange at a desired target. Speed and precision are the objectives when using such arms as the M4 (described in the cited operations manual) in one of its many variations and embodiments. A number of these embodiments are listed in the subject cited operations manual. However, there are many types of magazine-fed weapons with similar characteristics, and the discussion of conventional art is not limited to the M4 family. 
         [0003]    The major difficulty hindering the rapid fire of such weapons on a designated downrange target is the reloading cycle. The pauses or “downtime” occurring during the reloading cycle not only hinders the effective application of fire on a given target but also exposes the weapon operator to increased danger since he cannot protect himself during those pauses. If the weapon operator is engaged in competitive target shooting, the extra steps and the time expended for the reloading operations, may put the weapon operator at a competitive disadvantage. 
         [0004]    There have been many techniques for dealing with this drawback. These include larger magazines, such as large “banana” magazines, and connecting magazines together so that it is easier to lay hands on the new magazine once the old one is expended. In many cases, infantry tactics mandate staggered firing and reloading cycles so that weapon operators might protect themselves more effectively during the pause caused by the reloading cycle. While some of these techniques have been moderately effective, they are in general complicated, and do not substantially decrease the pause in firing required by the reloading cycle. In particular, none of these techniques encompass the automatic ejection of the spent magazine from a weapon such as the M4 (and its many variations and derivations from the original AR15/M16). 
         [0005]    When using the M4 (or one of its many variations), for example, it is necessary for the final round to be fired, and for the weapon operator to press a release button with one hand while pulling the spent magazine out with the other. Then, the operator could drop the spent magazine, grab a new (i.e., loaded) magazine and slide it into the magazine receiver or magazine well of the weapon. The operator would then have to take the added step of pulling back on the bolt to put a new round in the firing chamber or, in the case of most automatic weapons, press a bolt release to automatically load the next round, before firing again. 
         [0006]    Under the pressure of combat use, “anything that can go wrong will go wrong” during this reloading pause. Accordingly, it is extremely important to make this pause as short as possible while reducing the number of physical movements that the operator of the weapon must carry out to effect reloading. While competitive rapid-fire shooting does not embody the stresses of combat, the desire for rapid, accurate fire is still present. Because of this, competitive shooters do everything that can be done to limit the number of operations to be conducted for reloading, and to limit the time that the weapon is off target. 
         [0007]    Accordingly, a fast and efficient simplification of the reloading cycle is needed to reduce the number of steps that the weapon operator must take during the reloading process for the ultimate purpose of reducing the time necessary for the process. Moreover, automation of this process will benefit the weapon operator, especially if he/she is in a combat situation and/or time limited completion. 
       SUMMARY OF THE INVENTION 
       [0008]    It is a primary goal of the present invention to facilitate the reloading operation of an M4 rifle or one of its many variations. 
         [0009]    It is another object of the present invention to eliminate any changes to the weapon while accommodating the present invention. 
         [0010]    It is a further object of the present invention to facilitate the operation of the present invention with minimum alterations to standard weapons magazines. 
         [0011]    It is an additional object of the present invention to reduce the number of physical operations or steps that a weapons operator must carry out when undergoing the reloading operation. 
         [0012]    It is still another object of the present invention to provide an automatic release for the ammunition magazine once the last round from the magazine enters the weapon&#39;s firing chamber. 
         [0013]    It is still a further object of the present invention to provide an automatic magazine release system that provides for easy, automatic removal of the magazine from the weapon. 
         [0014]    It is again an additional object of the present invention to provide an automatic magazine release system that can be accommodated by modification to an otherwise standard magazine follower. 
         [0015]    It is again another object of the present invention to provide an effective automatic magazine release system that can be facilitated by an innovative modification to a standard magazine housing. 
         [0016]    It is still another object of the present invention to provide an automatic magazine release system that can be adapted to a wide range of magazine-fed automatic and semi-automatic weapons. 
         [0017]    It is yet a further object of the present invention to provide a system for removing ammunition magazines, requiring fewer steps and movements by the weapon operator. 
         [0018]    It is still an additional object of the present invention to provide an ammunition magazine release system that allows the weapon operator to remain on target. 
         [0019]    These and other goals and objects of the present invention are achieved by an ammunition magazine configured for weapons designed to received ammunition magazines, where each of the weapons has an ammunition magazine catch to hold the ammunition magazine within a magazine receiver or, more commonly known as, magazine well. The ammunition magazine has an outer casing and a follower within the outer casing. The outer casing includes at least one aperture in a side wall of the casing, where the aperture is positioned to align with the ammunition magazine catch in the weapon. The follower includes a spring-driven prong positioned to extend through the aperture when the follower reaches a predetermined position within the ammunition magazine casing. 
         [0020]    Another embodiment of the present invention includes a method for automatically ejecting a spent ammunition magazine from a weapon configured to receive an ammunition magazine. The method includes the steps of expending rounds from the ammunition magazine into the weapon until the last one of the rounds leaves the magazine. Simultaneous to the last round leaving the ammunition magazine, a spring-driven prong is extended perpendicularly through a side wall of the ammunition magazine so that the spring-driven prong activates a magazine catch mechanism to release the ammunition magazine from the weapon. The released magazine will then fall from the magazine well. 
         [0021]    A third embodiment of the present invention is directed to an interactive system for automatically removing an ammunition magazine from a weapon. The system includes a magazine receiver or well configured to hold an external magazine and to provide access between the ammunition magazine and a firing chamber of the weapon for rounds in the ammunition magazine. The ammunition magazine includes a casing with a holding lip arranged on a predetermined side of the ammunition magazine. A manual magazine release mechanism interfaces with the holding lip to hold the ammunition magazine casing within the magazine receiver. An aperture is positioned adjacent to the holding lip on the ammunition magazine casing. A spring-driven follower is arranged in the ammunition magazine casing and is movable therethrough. The spring-driven follower includes an inner structure or body having a concavity. A spring-loaded prong is arranged within the concavity to extend through the aperture when the follower moves to a predetermined position within the magazine casing, i.e., preferably when the last round leaves the magazine. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    The drawings included herewith are for the purpose of illustration only and not as a definition of the limits of the instant invention, for which reference should be made to the claims appended hereto. Other features, objects and advantages of this invention will become clear from the following more detailed description made with reference to the drawings in which: 
           [0023]      FIG. 1  is a side view of the type of conventional weapon in which the present invention can operate. 
           [0024]      FIG. 2  is an exploded view of a portion of the weapon depicted in  FIG. 1  identifying those parts of the conventional weapon that interact with the present invention. 
           [0025]      FIG. 3A  is a perspective view of a conventional outer casing for an ammunition magazine. 
           [0026]      FIG. 3B  is a perspective depiction of the interior parts of a convention ammunition magazine. 
           [0027]      FIG. 4  is a perspective view of a conventional ammunition magazine, depicting multiple rounds or shells contained within the outer casing, and a mechanism on the outer casing for interfacing with the weapon of  FIG. 1 . 
           [0028]      FIG. 5  is a partial side view of the conventional weapon, opposite of  FIG. 1 , depicting the lines for cutaways for sectional views. 
           [0029]      FIG. 6  is the sectional view taken at the position depicted in  FIG. 5 , illustrating an empty conventional magazine held in an operating position within a magazine well of the weapon. 
           [0030]      FIG. 6A  is a detailed or magnified view of part of  FIG. 6 , emphasizing the details of the upper portion of the magazine follower and the magazine catch of the weapon interfacing with the magazine. 
           [0031]      FIG. 7  is a top sectional view along the lines depicted in  FIG. 5 , including an empty conventional magazine contained within the weapon. 
           [0032]      FIG. 7A  is a magnified or detailed view of a portion of  FIG. 7 , depicting parts of the conventional magazine follower. 
           [0033]      FIG. 8  is an exploded view of a magazine follower modified in accordance with an embodiment of the present invention. 
           [0034]      FIG. 9  is a perspective view of the assembled magazine follower modified in accordance with the embodiment of the invention shown in  FIG. 8 , depicted in a manner to operate the magazine catch of a weapon containing the magazine. 
           [0035]      FIG. 10  is a perspective view of a magazine modified in accordance with the embodiment of the invention shown in  FIGS. 8 and 9 , and containing rounds or ammunition shells. 
           [0036]      FIG. 11  is a perspective view of a magazine modified in accordance with the embodiment of the invention shown in  FIGS. 8 and 9 , depicted in a configuration in which all of the rounds or ammunition shells have been expended from the magazine. 
           [0037]      FIG. 12  is the same view as  FIG. 6 , but in this case, depicting the ammunition magazine modified in accordance with the preferred embodiment of the present invention, where the magazine still contains four rounds. 
           [0038]      FIG. 12A  is an enlarged view of part of  FIG. 12  depicting the magazine modified in accordance with the same embodiment of the invention. 
           [0039]      FIG. 13  is the same sectional view as  FIG. 6 , but now containing the ammunition magazine modified in accordance with the preferred embodiment of the invention, and in which all rounds or shells have been expended from the magazine. 
           [0040]      FIG. 13A  is a magnified or detailed view of a portion of  FIG. 13 . 
           [0041]      FIG. 14  is a detailed view as depicted in  FIG. 13 , in which the invention has tripped the magazine release, and the magazine is able to move downward by gravity so as to fall out of the magazine well of the weapon. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0042]    The present invention is directed to modifications of various ammunition magazines that are used in weapons such as the M4, and its many variations, dating from the AR15/M16 to the present embodiments. Submitted as prior art of this application is the instruction manual for the Bushmaster family of weapons. For illustrative purposes, parts of the Bushmaster manual dated 2005 have been incorporated with the drawings of the present invention, namely  FIGS. 1-7A , as background for the application to better describe the present invention to such firearms. 
         [0043]    The present invention is directed to an interactive system between a weapon and ammunition magazine modified from the prior art. While the modifications to the magazine depicted in the drawings have been made to specifically fit the M4 family of weapons, other magazine-fed weapons can also be adapted by incorporating the same modifications to the ammunition magazine in accordance with the present invention. In particular, the weapon to benefit from the present invention will preferably include a manual magazine release mechanism. Alterations to the ammunition magazine can then be made to correspond to the location of the magazine catch and release mechanism on the weapon. The M4 Bushmaster is used in the present application because of the easy adaptability of the present invention to this particular weapon. However, the present invention is not limited thereto. 
         [0044]    For purposes of clarity, only those parts of the weapon that interact as part of the present invention are designated. The other parts of the weapon are depicted in the drawings, but are not designated since they do not interact as part of the inventive system. For example, in conventional art  FIG. 1 , illustrative weapon  100  has only a limited number of parts identified. These are the magazine receiver or well  110 , magazine release button  101 , and external ammunition magazine  10 . The external magazine  10  is depicted as being within magazine receiver/well  110  for purposes of operating the inventive interactive system. 
         [0045]    Conventional art  FIG. 2  is an exploded view of a portion of the weapon lock that is most relevant to the present invention. The parts depicted therein are found in a conventional M4 rifle. Those parts that relate to the interactive system include magazine release button  101  and magazine catch spring  102 . Magazine release catch  104  is connected to the magazine release button  101  through an aperture  121  in the weapon block or housing  120 . The magazine catch  104  includes a holding extension  105  which interfaces with the external magazine  10  (not shown in  FIG. 2 ). It is noted that the present invention eliminates the need to manually operate magazine release button  101 . 
         [0046]    In normal operation, the weapon operator must manually press magazine release button  101  to operate the magazine catch  104  and thus the holding extension  105  that holds the magazine to the weapon. Once the magazine release button is pressed, it is possible to pull ammunition magazine  10  from the magazine well  110 . Both of these conventional operations require extra movement on the part of the weapon operator, and as a result, the weapon cannot be held on target. Further, an often unacceptable span of time is needed before the weapon can be put back on target, due to the fact that both of the weapon operator&#39;s hands are necessary to carry out the removal of the spent ammunition magazine  10 . 
         [0047]    A conventional ammunition magazine is depicted in  FIGS. 3A, 3B and 4 . The magazine  10  depicted is adapted specifically for the M4 weapon. Accordingly, the inventive modifications for the interactive system in this illustration are depicted for this particular type of ammunition magazine, but the same concept can be applied to other weapon types with similarly configured magazines with modest changes and equivalencies. Moreover, the conventional ammunition magazine of  FIGS. 3A and 3B  includes a casing  11  and a follower  14 . A base plate  12  is provided to support a spring  13 , which drives follower  14 . At the top of follower  14  is an upper support  15  to hold rounds, and a spacer  151  so that a double row of off-set rounds can be placed in magazine  10 . This is best depicted in  FIG. 4 , where the double row of rounds  300  is vertically off-set from each other. This off-set configuration is shown more clearly in  FIGS. 12 and 12A . Upper curl  111  of casing  11  keeps the rounds  300  in place and positioned to enter the firing chamber of the weapon  100 . 
         [0048]    The conventional casing  11  of ammunition magazine  10  also includes an aperture  16  and a lip  17 . Both of these structures are sized and located to interact with holding extension  105  of magazine catch  104 . This is the structure that conventionally holds the magazine within the magazine receiver  110  of weapon  100 . When the operator pushes the magazine release button  101 , the entire magazine catch is moved outward away from the magazine well  110  (i.e., the magazine holding extension  105  is pushed away from catch lip  17  on the magazine). This action allows the operator to then pull out magazine  10  from the magazine receiver  110 . 
         [0049]    Conventional art  FIG. 5  depicts a side view of weapon  100  as viewed from the opposite side of the view in  FIG. 1 . The purpose of this figure is to better illustrate and locate lines  6 - 6  and  7 - 7  for the sectional views of  FIGS. 6, 6A, and 7, 7A , respectively. 
         [0050]      FIG. 6  is a sectional view depicting ammunition magazine  10  contained in magazine receiver/well  110  at a time when the magazine is empty. This is depicted by the location of upper support  15  of follower  14 . Spring  13  is fully extended. It should be noted that holding extension  105  is in place over lip  17  (shown in  FIG. 10 ), and extending into aperture  16  of magazine  10 . This interaction is enlarged and more closely depicted in  FIG. 6A . In the conventional art, even with the ammunition magazine  10  empty, it is firmly held in place by holding extension  105  until the magazine release button  101  is pushed by the weapon user. This same arrangement is depicted in conventional art  FIGS. 7 and 7A . In these Figures, the entire body of magazine catch  104  is clearly depicted in a manner which will keep holding extension  105  in position against catch lip  17  to hold the ammunition magazine  10  in position after the last round ( 300  in  FIG. 4 ) has been expended from the ammunition magazine  10  and into weapon  100 . 
         [0051]      FIG. 8  depicts a follower  14  modified in accordance with the present invention. Conventional followers typically have spacing arms  147 ,  148 ,  149  to properly maintain the follower  14  in position within magazine casing  11 . These spacer arms are necessary in conventional weapons to prevent the upper support  15  from being pushed too far into magazine casing  11 , and ensure that the follower  14  is guided properly in its upward movement as the rounds  300  are expended. Even if a conventional follower is not provided with spacing arms  147 ,  148 ,  149 , these could be added to facilitate installation of the structure that facilitates the present invention. 
         [0052]    Inset body  141 , as depicted in  FIG. 8 , is inserted between spacer arms  147  and  148 . Inset body  141  contains a concavity  142  in which a drive spring  144  and release prong  143  are placed. Release prong  143  extends through face plate  145 , which is attached to the insert body  141  by means of screws  146   a ,  146   b ,  146   c  and  146   d  or other securing fastener. The assembled version of the modified follower  14  is depicted in  FIG. 9 . 
         [0053]    During the normal operation of magazine  10 , spring  13  pushes the follower  14  upwards as rounds  300  are expended. During this time, release prong  143  is held back against the tension of drive spring  144  by the interior of magazine casing  11 . This relationship is depicted in  FIGS. 12 and 12A , in which rounds  300  are still within ammunition magazine  10 .  FIG. 12A  is a magnified partial view of  FIG. 12 , which depicts a sectional view shown along the lines  6 - 6  of conventional art  FIG. 5 . It would be clear to one skilled in this particular technology that other than insert piece  141 , containing drive spring  144  and release prong  143 , the follower  14  operates in the same manner as a conventional follower in a conventional ammunition magazine  10 . 
         [0054]    In order for the release prong  143  to operate interactively with the relevant parts of weapon  100 , it is necessary for the preferred embodiment of the present invention include certain modifications to the ammunition magazine  10  and casing  11 .  FIGS. 10 and 11  depict the necessary modifications. In  FIG. 10 , rounds  300  are still within ammunition magazine  10 . In  FIG. 11 , the last round  300  has been expended from ammunition magazine  10 , and the upper support  15  is at the very top of the ammunition magazine casing  11  with convex spacer  151  resting against upper curl  111  of casing  11 . The operation of the ammunition magazine casing  11  that constitutes part of the present invention includes the use of conventional catch aperture  16 , through which release prong  143  extends when all of the rounds  300  are expended from ammunition magazine  10 , as depicted in  FIG. 11 . 
         [0055]    To be clear, during the operation of the weapon and the movement of follower  14  within casing  11 , release prong  143  is held back by the interior of casing  11 . This is depicted in  FIGS. 12 and 12A . Once the last round  300  is expended from the ammunition magazine  10 , release prong  143  extends through catch aperture  16 , and by virtue of the bias provided by drive spring  144 , release prong  143  presses against holding extension  105  of weapon  100 . The holding extension  105  holds the magazine with the aid of lip  17 . The present invention includes release prong  143  which pushes holding extension  105  back away from catch aperture  16  and catch lip  17  to automatically release the magazine. This occurs when all of rounds  300  are expended from the magazine, and the magazine follower  14  is in the position depicted in  FIGS. 13 and 13A . 
         [0056]    Once release prong  143  has pushed back the magazine catch holding extension  105 , as depicted in  FIGS. 13 and 13A , the ammunition magazine  10  begins to slide downward due to the force of gravity as shown in  FIG. 14 . Because the magazine catch body  104  is spring biased, there is likelihood that magazine catch holding extension  105  will press back against the magazine since it is no longer being forced outward by release prong  143 , which has dropped below the plane of the magazine catch holding extension  105 , as depicted in  FIG. 14 . In order to prevent magazine catch holding extension  105  from interfering with the downward movement of magazine  10 , the ammunition magazine casing  11  is preferably modified to include a small stop  19  and a slot or depression  18  in the casing  11 . This slot or depression  18  is inset of sufficient depth so that magazine catch holding extension  105  cannot extend, contact and exert force/friction against the magazine casing  11 , which would hinder the drop of the ammunition magazine  10  from the weapon  100 . This relationship is depicted best in  FIG. 14 , in which it is clear that magazine catch holding extension  105  has insufficient extension to contact and grab any part of the magazine  10 , once the magazine catch holding extension is aligned within the slot or depression  18 . 
         [0057]    Moreover, with this invention, it will be appreciated that the weapon operator does not have to press magazine release button  101 , or pull ammunition magazine  10  from the magazine receiver  110 . Rather, the entire operation is made automatic by the present invention as described. Once the last round  300  leaves ammunition magazine  10 , whether this last round  300  has been fired or not, the automatic release and drop of the ammunition magazine  10  will occur without any efforts on the part of the weapon operator. This means that the weapon operator can keep both hands in firing position and maintain the sighting of the weapon downrange. 
         [0058]    To reload, the weapon operator need only grab a new ammunition magazine  10  and “slam it home” into the magazine receiver  110 . This can be done while the weapon operator maintains the sighting of the weapon downrange. 
         [0059]    It should be appreciated that the present invention constituted by inset body  141 , which includes release prong  143  and drive spring  144 , can be provided to a conventional follower  14  as a retrofit. Likewise, conventional ammunition magazine  10  can be modified to create slot  18  and stop  19 . As such, the present invention can be incorporated without substantial retooling by the primary weapons manufacturing facilities. Even if such retooling occurs, these are minor modifications to the ammunition magazine casing  11  with the inset body  141  being a separate piece that can be added to follower  14  at a later time. The addition of the present invention need not impose a substantial manufacturing burden. 
         [0060]    While the preferred embodiments have been described by way of example, the present invention is not limited thereto. Rather, the present invention should be understood to include any and all limitations, modifications, variations, embodiments, derivations, and adaptations that would occur to one skilled in this technology after understanding the present invention. Accordingly, the present invention should be limited only by the breadth of the following claims. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.