Abstract:
The invention is an improvement to a typical firearm drum magazine cartridge feeding system. The improvement provides firearm drum magazine feeding systems with features that work together in tandem to actuate a typical firearm bolt catch. The firearm bolt catch is a common feature in many firearms with the purpose of halting the forward momentum of a firearm bolt. By actuating the firearm bolt catch, a firearm operator is aware that a drum magazine is empty of firearm cartridges. The advantage of this improvement is twofold. First, a firearm enthusiast or soldier utilizing a drum magazine with this improvement will enjoy the benefit of not taking an additional step to pull back a firearm bolt before reloading, and any person will enjoy the added safety benefit of knowing when a firearm is unloaded and safe to handle.

Description:
[0001]    This application claims priority to provisional application No. 61/996,472 filed on May 9, 2014, which is hereby incorporated by reference in its priority. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention is directly related to firearms, and the feeding of non-linked cartridges in semi-automatic and automatic small arms. More particularly, the invention expands on high capacity drum magazines by including a feature with the function of actuating a firearm bolt catch. 
       BACKGROUND OF THE INVENTION 
       [0003]    Firearms have made significant advancements since the discovery of gunpowder in the ninth century. Although early firearm technologies like the musket of the 1700 and early 1800s offered a person the ability to strike a target at distance, they did not offer great accuracy. Additionally, these firearm technologies lacked the ability to reload rapidly, risking a person&#39;s life in a battle. In other situations, like hunting for example, many game opportunities were lost because of a slow reloading time. Thus, the search for a faster reload time and greater accuracy ensued. 
         [0004]    By the mid 1800s, a single barreled “repeating rifle” with cartridges was developed. This technology offered a person reduced reload time with the incorporation of a lever, and greater accuracy by using cartridges. Box magazines were developed with the function of housing multiple cartridges providing a person with multiple rounds before reloading. These early box magazines held the cartridges in a vertical stack above, below or in a horizontal stack to the side of the firearm. In other words, the cartridges sit one on top of another, pushed up by a spring, in a single file. To incorporate additional rounds in these types of box magazines necessitated a longer box magazine. Eventually, these box magazines can become too long to the point of becoming cumbersome. 
         [0005]    Drum magazines were developed in part to provide a greater cartridge capacity for a firearm while staying within a more compact area in relationship to the firearm. Drum magazines house cartridges in round or curved housings with a tension spring that pushed the cartridges around a curved track into a firearm chamber. The amount of cartridges housed within the drum magazine can be increased substantially while keeping a more compact profile. 
         [0006]    Many firearms today incorporate a feature typically referred to as a bolt catch. The bolt catch is an apparatus that prevents or “catches” a firearm bolt from moving forward in a firearm chamber. The bolt catch is automatically pushed into the firearm chamber, after a final cartridge is discharged, by a spring loaded feeder incorporated in a typical box magazine. When a firearm operator reloads the firearm with a fully loaded box magazine, typically the firearm operator will manually actuate the bolt catch to allow the bolt to move forward into chamber. 
         [0007]    Drum magazines used with a firearm that includes a bolt catch do not have the ability to actuate the bolt catch. Thus, when a final cartridge is discharged from a firearm, a firearm bolt will still move forward within a firearm chamber. During times when reloading rapidly with drum magazines is essential, having to pull the firearm bolt back manually before reloading another drum magazine puts an unnecessary and inconvenient burden on a person. Additionally, any person would not know whether a firearm is loaded or not loaded after discharging any amount of rounds from a drum magazine. Both of the above mentioned issues are safety concerns and need to be addressed. 
         [0008]    Therefore, there is a need to incorporate a bolt catch actuator within a drum magazine. This feature will provide any person with the convenience of more rapid reloading as well as the added safety benefits of knowing when a firearm is loaded or not loaded. 
       SUMMARY OF THE INVENTION 
       [0009]    An embodiment of the present invention includes an improvement to a typical firearm drum magazine cartridge feeding system. It is designed to improve firearm drum magazine feeding systems by introducing features that work together to actuate a firearm bolt catch integrated with semi-automatic and automatic firearms. The advantage of this improvement is twofold. First, a firearm enthusiast or soldier utilizing a drum magazine with this improvement will enjoy the benefit of not taking an additional step to pull back a firearm bolt before reloading, and any person will enjoy the added safety benefit of knowing when a firearm is unloaded and safe to handle. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0010]    The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
           [0011]      FIG. 1  is a front inside view of a spring body section  1  of a typical drum magazine used for loading ammunition into firearms. 
           [0012]      FIG. 2  is a front outside view of a channel body section  2  of a typical drum magazine, with a drum magazine neck slide  7  shown. 
           [0013]      FIG. 3  is a front inside view of a channel body section  2  of a typical drum magazine, with a drum magazine neck slide  7  shown in dotted lines. 
           [0014]      FIG. 4  is a first embodiment front inside view of a spring body section  1  of a typical drum magazine used for loading ammunition into firearms. 
           [0015]      FIG. 5  is a first embodiment front outside view of the channel body section  2  of a typical drum magazine, with a drum magazine neck slide  7  shown. 
           [0016]      FIG. 6  is a first embodiment front outside view of the channel body section  2  of a typical drum magazine, with the drum magazine neck slide  7  shown. 
           [0017]      FIG. 7  is a first embodiment front inside view of a channel body section  2  of a typical drum magazine, with the drum magazine neck slide  7  shown in dotted lines. 
           [0018]      FIG. 8  is a first embodiment outside perspective view of the drum magazine neck  6  of the channel body section  2 , of a typical drum magazine. 
           [0019]      FIG. 9  is a first embodiment outside perspective view of the drum magazine neck  6  of the channel body section  2 , of a typical drum magazine. 
           [0020]      FIG. 10  is a first embodiment side view of a typical drum magazine and the drum magazine neck  6  inserted into a typical firearm  18 . 
           [0021]      FIG. 11  is a first embodiment side view of a typical drum magazine and the drum magazine neck  6  inserted into a typical firearm  18 . 
           [0022]      FIG. 12  is a second embodiment front inside view of the spring body section  1  of a typical drum magazine used for loading ammunition into firearms. 
           [0023]      FIG. 13  is a second embodiment front outside view of the channel body section  2  of a typical drum magazine, with the neck slide  7  shown. 
           [0024]      FIG. 14  is a second embodiment front inside view of the channel body section  2  of a typical drum magazine. 
           [0025]      FIG. 15  is a second embodiment front inside close-up view of the channel body section  2  of a typical drum magazine. 
           [0026]      FIG. 16  is a second embodiment front inside close-up view of the channel body section  2 , of a typical drum magazine. 
           [0027]      FIG. 17  is a second embodiment outside perspective view of the drum magazine neck  6  of the channel body section  2 , of a typical drum magazine. 
           [0028]      FIG. 18  is a second embodiment outside perspective view of the drum magazine neck  6  of the channel body section  2 , of a typical drum magazine. 
           [0029]      FIG. 19  is a second embodiment side view of the drum magazine and the drum magazine neck  6  inserted into a typical firearm  18 . 
           [0030]      FIG. 20  is a second embodiment side view of the drum magazine and the drum magazine neck  6  inserted into a typical firearm  18 . 
           [0031]      FIGS. 21A and 21B  are piece-part side views of the first and second embodiments of the bolt catch actuator  11  and their associated modes of action. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0032]      FIG. 1  is a front inside view of a spring body section  1  of a typical drum magazine used for loading ammunition into firearms. The spring body section  1  may be attachable to a channel body section  2  with screws, bolts, studs, snap-fits or by another means that provides a compression or holding force between the spring body section  1  and the channel body section  2 . In the preferred embodiment, the drum magazine, as related to the present invention, is designed for a repeating rifle. Other embodiments may include drum magazines, as related to the present invention, designed for any type of firearm capable of utilizing a drum magazine. In the present invention, the drum magazine in the preferred embodiment contains a “clock” or “spiral” spring arm  3  contained within a main drum magazine body  4 . The spring arm  3  forces a multitude of magazine followers  5  upward and into a drum magazine neck  6 . In other embodiments another type of spring may be integrated into the drum magazine that which may provide the same function. Other embodiments may include another method of forcing a multitude of magazine followers upward and into the drum magazine neck and still remain within the scope of the present invention. 
         [0033]      FIG. 2  is a front outside view of a channel body section  2  of a typical drum magazine, with a drum magazine neck slide  7  shown. The channel body section  2  may be attachable to a spring body section  1  with screws, bolts, studs, snap-fits or by another means that provides a compression or holding force between the spring body section  1  and the channel body section  2 . The drum magazine neck slide  7  is integrated onto the outside of the drum magazine neck  6 . The drum magazine neck slide  7  guides the drum magazine neck  6  into a magazine well of a firearm. 
         [0034]      FIG. 3  is a front inside view of a channel body section  2  of a typical drum magazine, with the drum magazine neck slide  7  shown in dotted lines. A drum magazine channel  8  guides the multitude of magazine followers  5  upward and into the drum magazine neck  6 . 
         [0035]      FIG. 4  is a first embodiment front inside view of a spring body section  1  of a typical drum magazine used for loading ammunition into firearms. Here, a multitude of magazine followers  5  are led by a main magazine follower  9  comprised of a main magazine follower engagement member  10   a.  In this embodiment, the main magazine follower  9  leads the multitude of magazine followers  5 , and makes direct contact with a final ammunition round loaded into the drum magazine. The multitude of magazine followers  5  and main magazine follower  9  are forced into a drum magazine neck  6  by a spring arm  3 . In this embodiment the main magazine follower engagement member  10   a  is a magnetic material that engages with a bolt catch actuator engagement face  12  on a bolt catch actuator  11 . In this embodiment, the bolt catch actuator engagement face  12  includes an engagement segment  13   a  made of a magnetic material. The main magazine follower engagement member  10   a  magnetically engages with the engagement segment  13   a  of the bolt catch actuator engagement face  12  when the spring arm  3  forces the multitude of magazine followers  5  into the drum magazine neck  6 . In this embodiment, the main magazine follower engagement member  10   a  and the engagement segment  13   a  may be of any type of material capable of producing or being induced with a magnetic field including, but not limited to, typical ferromagnetic, paramagnetic and diamagnetic materials. Additionally, the bolt catch actuator engagement face  12  may be comprised of any of these types of magnetic material. Likewise, the bolt catch actuator  11  may be comprised of any of these types of material. In other embodiments, the main magazine follower  9  comprised of the main magazine follower engagement member  10   a  may be any magazine follower linked to the multitude of magazine followers  5 , other than a magazine follower in direct contact with a final ammunition round contained within the drum magazine. In these embodiments, the magazine follower in direct contact with the final ammunition round is considered one of the multitude of magazine followers  5 , whereas another magazine follower with the main magazine follower engagement member  10   a,  is referred to as the main magazine follower  9 . 
         [0036]      FIG. 5  is a first embodiment front outside view of a channel body section  2  of a typical drum magazine, with a drum magazine neck slide  7  shown. The drum magazine neck slide  7  is integrated onto the outside of the drum magazine neck  6 . The drum magazine neck slide  7  guides the drum magazine neck  6  into a magazine well of a firearm. In this embodiment, the bolt catch actuator  11  is slidably disposed within the drum magazine neck slide  7 . The bolt catch actuator  11  is shown here in a resting position. The bolt catch actuator  11  is a mechanically separate piece from the drum magazine neck slide  7 . 
         [0037]      FIG. 6  is the first embodiment front outside view of the channel body section  2  of a typical drum magazine, with the drum magazine neck slide  7  shown. The drum magazine neck slide  7  is integrated onto the outside of the drum magazine neck  6 . The drum magazine neck slide  7  guides the drum magazine neck  6  into a magazine well of a firearm. In this embodiment, the bolt catch actuator  11  is slidably disposed within the drum magazine neck slide  7 . The bolt catch actuator  11  is shown here in an extended position with a bolt catch actuator arm  14  shown. Here, the bolt catch actuator  11  is mechanically separate from the drum magazine neck slide  7 . 
         [0038]      FIG. 7  is a first embodiment front inside view of a channel body section  2  of a typical drum magazine, with the drum magazine neck slide  7  shown in dotted lines. A drum magazine channel  8  guides the multitude of magazine followers  5  upward and into the drum magazine neck  6 . In this embodiment, the bolt catch actuator  11  is slidably disposed within the drum magazine neck slide  7 . The bolt catch actuator  11  is shown here in a resting position. The bolt catch actuator  11  is mechanically separate from the drum magazine neck slide  7 . The bolt catch actuator  11  is integrated with the bolt catch actuator engagement face  12 . In this embodiment, the bolt catch actuator engagement face  12  includes the engagement segment  13   a  that includes magnetic properties. The magnet may be of any type of material capable of producing or being induced with a magnetic field including, but not limited to, typical ferromagnetic, paramagnetic and diamagnetic materials. The magnet may be of any size and shape capable of fitting within the spatial constraints of the bolt catch actuator  11 . The magnet may be of any size and shape capable of magnetically engaging with the main magazine follower engagement member  10   a  and providing adequate force to move the bolt catch actuator  11  toward a firearm bolt catch  20 . 
         [0039]      FIG. 8  is a first embodiment outside perspective view of the drum magazine neck  6  of the channel body section  2 , of a typical drum magazine. In this embodiment, the bolt catch actuator  11  is slidably disposed within the drum magazine neck slide  7 . The bolt catch actuator  11  is shown here in a resting position. The bolt catch actuator  11  is mechanically separate from the drum magazine neck slide  7 . Ammunition rounds are fed along the drum magazine channel  8  by a force induced by the spring arm  3 . When the last round is discharged, the main magazine follower  9 , which is comprised of the main magazine follower engagement member  10   a,  moves across the bolt catch actuator engagement face  12  and the engagement segment  13   a.  The main magazine follower  9  and bolt catch actuator  11  magnetically engage causing the bolt catch actuator  11  to move toward the firearm bolt catch  20 . 
         [0040]      FIG. 9  is the first embodiment outside perspective view of the drum magazine neck  6  of the channel body section  2 , of a typical drum magazine. In this embodiment, the bolt catch actuator  11  is slidably disposed within the drum magazine neck slide  7 . The bolt catch actuator  11  is shown here in an extended position with the bolt catch actuator arm  14  showing. The bolt catch actuator  11  is mechanically separate from the drum magazine neck slide  7 . Ammunition rounds are fed along the drum magazine channel  8  by a force induced by the spring arm  3 . When the last round is discharged, the main magazine follower  9 , which is comprised of the main magazine follower engagement member  10   a,  moves across the bolt catch actuator engagement face  12  and the engagement segment  13   a.  The main magazine follower  9  and bolt catch actuator  11  magnetically engage causing the bolt catch actuator  11  to move toward the firearm bolt catch  20 . 
         [0041]      FIG. 10  is a first embodiment side view of a typical drum magazine and the drum magazine neck  6  inserted into a firearm  18 . In this embodiment the bolt catch actuator  11  is slidably disposed within the drum magazine neck slide  7 . The bolt catch actuator  11  is shown here in a resting position, before the main magazine follower  9  and the main magazine follower engagement member  10   a,  move across the bolt catch actuator engagement face  12  and the engagement segment  13   a.  The main magazine follower  9  and the bolt catch actuator  11  magnetically engage causing the bolt catch actuator  11  to move toward the firearm bolt catch  20  which halts the forward momentum of a firearm bolt  21 , housed within the firearm  18 . 
         [0042]      FIG. 11  is the first embodiment side view of a typical drum magazine and the drum magazine neck  6  inserted into a typical firearm  18 . In this embodiment the bolt catch actuator  11  is slidably disposed within the drum magazine neck slide  7 . The bolt catch actuator  11  is shown here in an extended position with the bolt catch actuator arm  14  shown, after the main magazine follower  9  and the main magazine follower engagement member  10   a,  move across the bolt catch actuator engagement face  12  and the engagement segment  13   a.  The main magazine follower  9  and bolt catch actuator  11  magnetically engage causing the bolt catch actuator  11  to move toward the firearm bolt catch  20  which halts the forward momentum of the firearm bolt  21 , housed within the firearm  18 . 
         [0043]      FIG. 12  is a second embodiment front inside view of a spring body section  1  of a typical drum magazine used for loading ammunition into firearms. Here, a multitude of magazine followers  5  are led by a main magazine follower  9  comprised of a main magazine follower engagement member  10   b.  The multitude of magazine followers  5  and the main magazine follower  9  are forced into the drum magazine neck  6  by a spring arm  3 . In this embodiment the main magazine follower engagement member  10   b  is a ball bearing attached to a spring  16  that engages with an engagement segment  13   b  of a bolt catch actuator engagement face  12 . Also in this embodiment, the engagement segment  13   b  of the bolt catch actuator engagement face  12  is a recessed channel shaped to engage with the main magazine follower engagement member  10   b.  The main magazine follower engagement member  10   b  mechanically engages with the bolt catch actuator engagement face  12  when the spring arm  3  forces the multitude of magazine followers  5  into the drum magazine neck  6 . In this embodiment, both the main magazine follower engagement member  10   b  and the bolt catch actuator engagement face  12  may be of any shape or material which provides a strong, temporary linkage between the main magazine follower engagement member  10   b  and the bolt catch actuator engagement face  12 . In other embodiments, the main magazine follower engagement member  10   b  may be a solid piece or solid pieces that are not spherical in shape, whilst still providing the same function of mechanically linking with the bolt catch actuator engagement face  12 . In other embodiments, the main magazine follower engagement member  10   b  may be a solid piece molded or shaped into the main magazine follower  9 , whilst still providing the same function of mechanically linking with the bolt catch actuator engagement face  12 . In these embodiments, the engagement segment  13   b  may be a lever, flange, fin or other component integrated or molded onto the bolt catch actuator engagement face  12 . 
         [0044]      FIG. 13  is a second embodiment front outside view of a channel body section  2  of a typical drum magazine, with a neck slide  7  shown. The drum magazine neck slide  7  is integrated onto the outside of the drum magazine neck  6 . The drum magazine neck slide  7  guides the drum magazine neck  6  into a magazine well of a firearm. In this embodiment, a bolt catch actuator  11  is slidably disposed within the drum magazine neck slide  7 . 
         [0045]      FIG. 14  is a second embodiment front inside view of the channel body section  2  of a typical drum magazine. A drum magazine channel  8  guides the multitude of magazine followers  5  upward and into the drum magazine neck  6 . In this embodiment, an engagement channel  17  provides a path for the main magazine follower engagement member  10   b  to slide into the engagement segment  13   b  on the bolt catch actuator engagement face  12 . 
         [0046]      FIG. 15  is a second embodiment front inside close-up view of the channel body section  2  of a typical drum magazine. The drum magazine channel  8  guides the multitude of magazine followers  5  upward and into the drum magazine neck  6 . In this embodiment, the engagement channel  17  provides a path for the main magazine follower engagement member  10   b  to slide into the engagement segment  13   b  on the bolt catch actuator engagement face  12 . In this embodiment, the bolt catch actuator  11  is in the resting position. The bolt catch actuator engagement face  12  is exposed in the engagement channel  17 . 
         [0047]      FIG. 16  is the second embodiment front inside close-up view of the channel body section  2  of a typical drum magazine. The drum magazine channel  8  guides the multitude of magazine followers  5  upward and into the drum magazine neck  6 . In this embodiment, the engagement channel  17  provides a path for the main magazine follower engagement member  10   b  to slide into the engagement segment  13   b  on the bolt catch actuator engagement face  12 . In this embodiment, the bolt catch actuator  11  is in the extended position. The bolt catch actuator engagement face  12  is exposed in the engagement channel  17 . 
         [0048]      FIG. 17  is a second embodiment outside perspective view of the drum magazine neck  6  of the channel body section  2 , of a typical drum magazine. In this embodiment, the bolt catch actuator  11  is slidably disposed within the drum magazine neck slide  7 . The bolt catch actuator  11  is shown here in a middle position. The bolt catch actuator  11  is mechanically separate from the drum magazine neck slide  7 . Ammunition rounds are fed along the drum magazine channel  8  by a force induced by the spring arm  3 . When the last round is discharged, the main magazine follower  9 , which is comprised of the main magazine follower engagement member  10   b,  moves across the bolt catch actuator engagement face  12  and the engagement segment  13   b.  The main magazine follower  9  and the bolt catch actuator  11  mechanically engage causing the bolt catch actuator  11  to move toward the firearm bolt catch  20 . 
         [0049]      FIG. 18  is the second embodiment outside perspective view of the drum magazine neck  6  of the channel body section  2 , of a typical drum magazine. In this embodiment, the bolt catch actuator  11  is slidably disposed within the drum magazine neck slide  7 . The bolt catch actuator  11  is shown here in the extended position. The bolt catch actuator  11  is mechanically separate from the drum magazine neck slide  7 . Ammunition rounds are fed along the drum magazine channel  8  by a force induced by the spring arm  3 . When the last round is discharged, the main magazine follower  9 , which is comprised of the main magazine follower engagement member  10   b,  moves across the bolt catch actuator engagement face  12  and the engagement segment  13   b.  The main magazine follower  9  and the bolt catch actuator  11  mechanically engage causing the bolt catch actuator  11  to move toward the firearm bolt catch  20 . 
         [0050]      FIG. 19  is a second embodiment side view of the drum magazine and the drum magazine neck  6  inserted into a firearm  18 . In this embodiment the bolt catch actuator  11  is slidably disposed within the drum magazine neck slide  7 . The bolt catch actuator  11  is shown here in a resting position, before the main magazine follower  9  and the main magazine follower engagement member  10   b,  move across the bolt catch actuator engagement face  12  and the engagement segment  13   b.  The main magazine follower  9  and bolt catch actuator  11  mechanically engage causing the bolt catch actuator  11  to move toward the firearm bolt catch  20  which halts the forward momentum of a firearm bolt  21 , housed within the firearm  18 . 
         [0051]      FIG. 20  is the second embodiment side view of the drum magazine and the drum magazine neck  6  inserted into a firearm  18 . In this embodiment the bolt catch actuator  11  is slidably disposed within the drum magazine neck slide  7 . The bolt catch actuator  11  is shown here in an extended position, after the main magazine follower  9  and the main magazine follower engagement member  10   b,  move across the bolt catch actuator engagement face  12  and the engagement segment  13   b.  The main magazine follower  9  and bolt catch actuator  11  mechanically engage causing the bolt catch actuator  11  to move toward the firearm bolt catch  20  which halts the forward momentum of the firearm bolt  21 , housed within the firearm  18 . 
         [0052]      FIGS. 21A and 21B  are piece-part side views of the first and second embodiments of the bolt catch actuator  11  and their associated modes of action. The first embodiment  21 A shows the main magazine follower  9  and the main magazine follower engagement member  10   a  attached to the multitude of magazine followers  5 . The main magazine follower engagement member  10  is made of magnetic material that engages with the engagement segment  13   a  of the bolt catch actuator engagement face  12  on the bolt catch actuator  11 . In the second embodiment  21 B, the main magazine follower  9  and the main magazine follower engagement member  10   b  are attached to the multitude of magazine followers  5 . The spring  16  forces the main magazine follower engagement member  10   b  into the engagement segment  13   b  of the bolt catch actuator engagement face  12  on the bolt catch actuator  11 .