This disclosure relates to accessories and components for use with firearms. More particularly, the present disclosure relates to an ammunition magazine for rimmed cartridges and a baseplate for the magazine.
Semiautomatic firearms, including handguns and long guns, use a detachable box magazine to feed ammunition into the chamber. The box-type magazine typically has a magazine tube that holds ammunition in a stack with projectiles of the ammunition pointing forward. A baseplate closes the bottom end of the tube and the upper end of the tube defines feed lips. A follower advances the ammunition towards the feed lips at the upper end of the tube due to the force of a spring between the baseplate and the follower. The magazine tube may be straight or curved, depending on the type of ammunition and its shape when stacked.
One aspect of the present disclosure is directed to a detachable box magazine for rimmed cartridges. Another aspect of the present disclosure is directed to a magazine assembly that includes a novel baseplate and magazine tube. Numerous embodiments and variations will be apparent in light of the present disclosure.
These and other features of the present embodiments will be better understood by reading the following detailed description, taken together with the Figures herein described. For purposes of clarity, not every component may be labeled in every drawing. Furthermore, as will be appreciated, the figures are not necessarily drawn to scale or intended to limit the present disclosure to the specific configurations shown. In short, the Figures are provided merely to show example structures.
Disclosed is a magazine for rimmed cartridges where the cartridges have a substantially parallel orientation when viewed from the side. Also disclosed is a magazine assembly that includes a baseplate and magazine tube, where the baseplate engages to a bottom end of the magazine tube, such as with a snap fit.
In one example embodiment, a magazine is configured for rimmed cartridges, such as .22LR ammunition. The magazine includes a magazine tube, a baseplate, a follower, and a spring, where the follower is biased toward the upper end of the tube by the spring. The inside faces of each lateral wall of the magazine tube include ribs that protrude inward and extend vertically along most of the length of the tube. A pair of opposed first ribs includes ribs on opposite sidewalls closer to the front of the magazine tube, where the first ribs are aligned and spaced apart laterally by a first distance. A pair of second ribs includes ribs extending inward from opposite sidewalls near the rear of the magazine tube, where the second ribs are aligned and spaced apart laterally by a second distance that is greater than the first distance. The ribs are sized and positioned to result in the cartridges stacking in a nominally parallel orientation when viewed from the side. When the magazine is loaded to capacity with ammunition, some cartridges in the magazine are arranged in two offset columns with axes of cartridges in adjacent columns generally converging when moving in a forward direction.
In another example, a magazine assembly includes a magazine tube and a baseplate. The baseplate is configured to attach to the base of the tube using a snap fit. In one such embodiment, the baseplate includes a pair of arms or tabs that extend upward from the plate of the baseplate. Each arm includes a hook or catch at its upper end. When the baseplate is advanced onto the lower end of the magazine tube along the tube axis, the arms are temporarily deflected outward and then snap into place with the catches occupying a recess defined in the surface of the magazine tube. For example, opposite lateral sides or the front and back of the magazine tube can define recesses to engage the catches. The baseplate may further define a recess useful to seat the magazine spring. Advantageously, such a design eliminates the need for a separate spring plate or retaining structure. Also, in some embodiments the baseplate can be recessed into the base and sides of the magazine tube when installed so that it is resistant to unintended disassembly, such as when the magazine is dropped.
The baseplate of a magazine assembly is often installed onto the magazine tube by sliding engagement with flanges at the lower end of the magazine tube. To prevent the baseplate from inadvertently sliding off of the tube, an additional plate (e.g., a spring plate) abuts the top surface of the baseplate and includes a protrusion that extends downward and into the baseplate. When installed into the tube, this interface between the spring plate and baseplate prevents removal of the baseplate due to the spring plate blocking the baseplate from sliding off of the flanges. This engagement between the spring plate and baseplate is one type of retention mechanism for a magazine baseplate.
To remove the baseplate, the user presses the post upward into the tube to disengage the spring plate from the baseplate, usually with a punch or similar tool. This action allows the baseplate to slide off of the flanged lower end of the tube. A challenge with such an assembly is that the sliding movement of the baseplate is transverse to the force of the magazine spring. As such, efforts to control removal of the baseplate can result in the spring unexpectedly springing from the tube when the baseplate is removed. Similarly, when assembling the magazine, the spring plate must be pushed into the tube against the force of the spring while trying to slide the baseplate over the flanged end of the tube.
In light of these challenges, it would desirable to simplify the magazine assembly, such as eliminating the need for a spring plate. It would also be desirable to have a magazine assembly that is easier to assemble, such as one where the baseplate is installed in a direction consistent with the spring force. Therefore, a need exists for improvements to a baseplate and magazine assembly. The present disclosure addresses this need and others by providing a magazine assembly that includes a baseplate configured to snap to the bottom of the magazine tube. In some such embodiments, the baseplate eliminates the need for a separate spring plate or for an interlocking arrangement of spring plate and base plate to retain the baseplate on the magazine tube.
Magazines for pistol ammunition (e.g., 9 mm, 45 ACP) are configured to retain the ammunition in a stack within the magazine tube. The ammunition may be arranged in a single stack or an offset double stack. The bottom-most cartridge contacts a follower, which is biased toward the feed lips by a spring between the baseplate and the follower. In many cases, the ammunition is “rimless” where the head of the cartridge has a rim that does not extend beyond the diameter of the casing body. Due to behaving like a cylinder, rimless ammunition stacks in a column with the cartridges in parallel and with casings of adjacent cartridges abutting one another along a majority of the case length. Due to the shape of the stack, the magazine tube is most often straight.
In contrast, rimmed ammunition includes a flanged rim at the head of the cartridge that extends beyond the diameter of the casing body. Examples of rimmed ammunition include .22 LR, .17 HMR, .38 Special, and some shotgun cartridges. Some rimmed ammunition (e.g., .22 LR) is referred to as “rimfire” ammunition due to the location and type of primer in the rim. The rim of rimmed cartridges is used to retain the cartridge in the chamber with proper head spacing. When stacked, however, the larger diameter of the rim causes the cartridges to stack in a curved arrangement, as viewed from the side, due to the difference in size between the rim and the casing body. Accordingly, the magazine tube is often curved to accommodate the curvature of the ammunition stack and sometimes referred to as a “banana magazine.”
One challenge is that the orientation of the central axis through the bottom cartridge changes as ammunition is depleted from the magazine. For example, the bottom-most cartridge in a banana magazine filled to capacity may be oriented at roughly 45° with respect to the bore axis while the top-most cartridge is oriented generally parallel to the bore axis. As ammunition is depleted, the follower moves along the curved tube with the top surface of the follower oriented with the cartridge above it.
A curved magazine has an increased propensity to result in feeding failures due to the block-shaped follower not moving smoothly through the curved tube. Additionally, the magazine spring in a curved magazine is often coiled along a linear axis, but when installed into a curved magazine tube results in an increased likelihood of a jam.
One approach to address challenges associated with rimfire magazines has been to stack the projectiles of the ammunition in a single column while skewing the heads in opposite directions. Although the heads have alternating orientations, such design results in a single, crisscrossed stack of ammunition, particularly as viewed from the front. Such design has reduced capacity since the magazine effectively is configured as a single stack magazine. Despite improvements in magazine design, many challenges still exist.
To address these challenges, the present disclosure provides a magazine for rimmed cartridges retained in a double stack arrangement, and where cartridges are substantially parallel as viewed from the side.
As will be appreciated in light of the present disclosure, and in accordance with some embodiments, ammunition magazines configured as described herein can be used in handguns or long guns alike. Further, concepts of the present disclosure can be applied to magazines for pistol ammunition, rimfire ammunition, rifle ammunition, and shotgun ammunition. In accordance with some example embodiments, a magazine configured as described herein can be utilized with a semiautomatic handgun chambered in .22 LR or other suitable ammunition. In accordance with other embodiments, a snap-fit base plate can be used with magazines for rimmed or rimless ammunition.
As discussed herein, terms referencing direction, such as upward, downward, vertical, horizontal, left, right, front, back, etc., are used for convenience to describe embodiments of a magazine in an upright orientation. Embodiments according to the present disclosure are not limited by these directional references and it is contemplated that magazines of the present disclosure could be used in any orientation.
It should also be noted that certain terminology is used herein for consistency and ease of understanding the present disclosure; however, the present disclosure is not limited to that specific terminology and alternate terms can be used to refer to the magazine and its components. For example, the disclosed magazine can alternately be referred to as a box magazine, an ammunition magazine, or other terms. Similarly, the disclosed floorplate can alternately be referred to, for example, as a bottom plate, a butt plate, a base plate, a magazine bottom, or other terms. As will be further appreciated, the particular configuration (e.g., materials, dimensions, etc.) of a magazine and its components configured as described herein may be varied, for example, depending on the intended use, type of ammunition to be retained, and firearm in which it will be used. Numerous configurations will be apparent in light of this disclosure.
The baseplate 130 is attached to a lower end portion 102b of the magazine tube with tabs 134 extending axially along the lower end portion 102b of the magazine tube 102. The baseplate 130 includes a base 132 that is generally planar, and tabs 134 that extend upward from opposite sides of the base 132. Although shown as extending up from opposite lateral sides of the base 132, the tabs 134 could alternately extend up from the front and back of the base 132. Each tab 134 is configured to engage a recess 120 in the magazine tube 102, such as a recess in the flange 116, sidewall 104, 106, front tube wall 108, and/or rear tube wall 110. The catch 136 and recess 120 provide a snap fit. For example, a top end of each tab 134 includes a catch 136 (shown in
A follower 150 is retained in the magazine tube 102 between the baseplate 130 and the feed lips 112 and is biased towards the feed lips 112 by a magazine spring 160. When loaded with ammunition, the follower 150 is between the baseplate 130 and the stack 80 of one or more rimmed cartridges 70. The follower 150 optionally includes one or more posts 152 that protrude from each side of the follower 150 through elongated openings 114 that extend vertically along sidewalls 104, 106 of the magazine tube 102. The posts 152 are shown as being cylindrical; however, other geometries can be used. When the follower 150 rises to the top of the magazine 100 when the magazine is empty, the post(s) 152 lifts the slide catch lever so that the slide is retained in slidelock. Additionally, the user can use the enlarged ends 153 to pull down the follower 150 when loading to facilitate loading the magazine 100.
In this example, the magazine 100 is shown loaded to capacity with rimmed cartridges 70. As discussed below in more detail, the stack 80 includes two offset columns of rimmed cartridges 70 when loaded to capacity. As can be seen from a side of the magazine 100, vertically adjacent cartridges 70 in each column are arranged in a substantially parallel orientation in the magazine tube 102.
Referring now to
The follower 150 is retained in the magazine tube 102 below the stack 80 and is biased upward toward the feed lips 112 (shown in
The stack 80 includes twenty cartridges 70 in this example, although the magazine 100 can be configured to hold other quantities of cartridges 70, including 10, 15, 18, 25, or 30, for example. The top end portion 102a of the magazine tube 102 tapers in lateral width towards the feed lips 112 (visible in
When the top of the magazine 100 and cartridges 70 are oriented horizontally, such as in
The follower 150 includes a follower body 151 with a front side 151a, a rear side 151b, a bottom side 151c, and a top side 151d. The front and rear sides 151a, 151b are aligned with the respective front wall and rear wall 110 of the magazine tube 102. The bottom side 151c is oriented generally perpendicular to the front and rear sides 151a, 151b. The top side 151d is substantially parallel to the axes of the cartridges 70 and defines angle R with the front side 151a of about 20°. The magazine spring 160 is positioned between the baseplate 130 and the bottom side 151c of the follower 150. The baseplate 130 is received between the front wall 108 and rear wall 110 and is flush with or recessed into the bottom of the magazine tube 102.
Referring now to
The follower body 151 is centered between the sidewalls 104, 106 with a lower part of the follower body 151 snugly fit between the sidewalls 104, 106 of the lower end portion 102b. Note in the lower end portion 102b that the sidewalls 104, 106 have an increased thickness and define flange 116. The posts 152 extend through the sidewalls 104, 106 and each has an enlarged end 153 that travels along an outside surface of the sidewalls 104, 106. In some embodiments, the post 152 and end 153 stop on the lower end portion 102b of the magazine tube 102 when in the lowest position. Similar to as shown in
The inside surfaces of sidewalls 104, 106 define ribs 170, 171, 172, 173 that extend inward. Each rib 170, 171, 172, 173 generally has a rounded profile, but a rectangular profile or other profile is also acceptable. Each rib 170, 171, 172, 173 is on the inside of the magazine tube 102 and extends along the magazine tube axis 101 for all or part of the height of the magazine tube 102. For example, ribs 170, 171, 172, 173 are present at least along portions of the magazine tube 102 where cartridges 70 are arranged or in two offset columns when the magazine 100 is filled to capacity, such as shown in
A first left rib 170 and a first right rib 171 are arranged in an opposed relationship and extend inward toward one another from opposite sidewalls 104, 106, respectively. The first left rib 170 extends inward from a forward portion the left sidewall 104 and the first right rib 171 extends inward from a forward portion of the right sidewall 106. The first left rib 170 and the first right rib 171 are laterally spaced by a first distance D1. The first left rib 170 and first right rib 171 contact the case 74 of the cartridges 70 just behind the mouth 76.
A second left rib 172 and a second right rib 173 arranged in an opposed relationship, where the second left rib 172 extends inward from a rear portion of the left sidewall 104 and the second right rib 173 extends inward from a rear portion of the right sidewall 106. The second left rib 172 and the second right rib 173 are laterally spaced by a second distance D2 that is greater than the first distance D1. The second left rib 172 and the second right rib 173 contact the case 74 of the cartridges closer to the rim 72. Distances D1 and D2 can be selected to achieve the desired stack geometry, such as the location where adjacent cartridges 70 make contact, and/or to provide the lateral spacing x1, x2 discussed above for projectiles 78 and rims 72.
The openings 114 along sidewalls 104, 106 are also shown. A post 152 extends from each side of the follower 150 through each opening 114 to an enlarged end 153 that travels on an outside of the opening 114 along the magazine tube 102 when the follower 150 advances through the magazine tube 102. As noted above, the post(s) 152 can actuate the slide catch lever when the magazine 100 is empty and also can be used by the user to pull down the follower 150 to facilitate loading the magazine 100.
As discussed above, the baseplate 130 includes a base 132 of generally planar geometry. Tabs 134 extend upward from opposite sides of the base 132 and include a catch 136 at the upper end. When installed onto the lower end portion 102b of the magazine tube 102, each catch 136 is received in the corresponding recess 120 defined in the sidewall 104, 106 and each tab 134 is recessed into the recess 117 defined in the sidewall of the magazine tube 102.
To install the baseplate 130, the user can seat the end of the magazine spring 160 into the spring recess 135, then push the baseplate 130 onto the lower end portion 102b of the magazine tube 102 along the direction of the magazine spring 160 or magazine tube axis 101 (shown in
The following examples pertain to further embodiments, from which numerous permutations and configurations will be apparent.
Example 1 is a magazine for rimmed cartridges, the magazine comprising a magazine tube having a front tube wall, a rear tube wall, a left tube sidewall, and a right tube sidewall. A first left rib and a first right rib extend along an inside of the magazine tube in an opposed relationship, where the first left rib extends inward from a forward portion of the left tube sidewall and the first right rib extends inward from a forward portion of the right tube sidewall, and where the first left rib and the first right rib are laterally spaced by a first spacing. A second left rib and a second right rib extend along an inside of the magazine tube in an opposed relationship, where the second left rib extends inward from a rear portion of the left tube sidewall and the second right rib extends inward from a rear portion of the right tube sidewall, and where the second left rib and the second right rib are laterally spaced by a second spacing that is greater than the first spacing. When the magazine is filled to capacity with rimmed cartridges, the magazine includes a stack of rimmed cartridges arranged in two offset columns with projectiles of the rimmed cartridges laterally spaced from a median plane by a first distance and rims of the rimmed cartridges laterally spaced from the median plane by a second distance that is greater than the first distance.
Example 2 includes the subject matter of Example 1, where, when filled to capacity, projectiles of the rimmed cartridges are arranged in two offset columns along the front tube wall of the magazine tube.
Example 3 includes the subject matter of Example 1 or 2, where when filled to capacity, except for a top-most cartridge, each cartridge in the magazine contacts a next highest cartridge in the stack near a mouth of a cartridge casing of the next highest cartridge.
Example 4 includes the subject matter of Example 1 or 2, where when filled to capacity, except for a top-most cartridge, a projectile of each cartridge in the magazine contacts a casing of a next highest cartridge in the stack near a mouth of the cartridge casing of the next highest cartridge.
Example 5 includes the subject matter of any of Examples 1-4, where the rimmed cartridges have a parallel orientation as viewed from a side of the magazine.
Example 6 includes the subject matter of any of Examples 1-5, where the first left rib and the first right rib contact a forward portion of shell casings in the stack and the second left rib and the second right rib contact a rear portion of shell casings in the stack.
Example 7 includes the subject matter of Example 6, where the forward portion of the shell casings is adjacent a mouth of the shell casings and wherein the rear portion of the shell casings is adjacent the rim of the shell casings.
Example 8 includes the subject matter of any of Examples 1, where, when filled to capacity, except for a top-most cartridge, a rim of cartridges in the stack are offset in an alternating fashion to one side of the median plane.
Example 9 includes the subject matter of any of Examples 1-8, where, except for the top-most cartridge, each cartridge in the magazine is offset from the median plane by 2-4°.
Example 10 includes the subject matter of any of Examples 1-9, where the top-most cartridge is centered between the left tube sidewall and the right tube sidewall and is aligned along the median plane.
Example 11 includes the subject matter of any of Examples 1-10, where an axis through each cartridge in the magazine defines a pitch angle of between 15-25° with respect to a horizontal when the front wall of the magazine tube is oriented vertically.
Example 12 includes the subject matter of Example 11, where the pitch angle is from 18° to 22°.
Example 13 includes the subject matter of any of Examples 1-12, where an axis through each cartridge in the magazine, except for the top-most cartridge, defines a yaw angle of ±2-5° with respect to the median plane.
Example 14 includes the subject matter of Example 13, where the yaw angle is about +3° or about −3°.
Example 15 includes the subject matter of any of Examples 1-14 and further comprises a baseplate configured to attach to the magazine tube using a snap fit.
Example 16 is a magazine comprising a magazine tube extending along a magazine axis from a lower end portion to a top end portion defining feed lips, and a baseplate configured to attach to the lower end portion of the magazine tube using a snap fit.
Example 17 includes the subject matter of Example 16, where the baseplate comprises a base having a generally planar geometry, tabs extending up from opposite sides of the base, and a catch on an upper end of each of the tabs.
Example 18 includes the subject matter of Example 18, where the opposite sides of the base include a left side and a right side or a front side and a rear side.
Example 19 includes the subject matter of any of Examples 16-18, where a bottom end of the magazine tube defines a recessed region sized and configured to receive the base of the baseplate so that the base is recessed into or flush with the bottom end of the magazine tube.
Example 20 includes the subject matter of any of Examples 16-19, where the lower end portion of the magazine tube defines a recess sized and configured to receive each of the tabs of the baseplate so that the tab is recessed into or is flush with the lower end portion.
Example 21 includes the subject matter of any of Examples 16-20 and further comprises a follower received in the magazine tube and a magazine spring between the follower and the baseplate.
Example 22 includes the subject matter of Example 21, where the baseplate defines a recess for the magazine spring.
Example 23 includes the subject matter of any of Examples 16-22, where the magazine tube and baseplate are made of a polymeric material.
Example 24 includes the subject matter of any of Examples 16-23, where the magazine tube has a front tube wall, a rear tube wall, a left tube sidewall, and a right tube sidewall. A first left rib and a first right rib extending along an inside of the magazine tube in an opposed relationship, where the first left rib extends inward from a forward portion of the left tube sidewall and the first right rib extends inward from a forward portion of the right tube sidewall, and where the first left rib and the first right rib are laterally spaced by a first spacing. A second left rib and a second right rib extend along an inside of the magazine tube in an opposed relationship, where the second left rib extends inward from a rear portion of the left tube sidewall and the second right rib extends inward from a rear portion of the right tube sidewall, and where the second left rib and the second right rib are laterally spaced by a second spacing that is greater than the first spacing. When the magazine is filled to capacity with rimmed cartridges, the magazine includes a stack of rimmed cartridges arranged in two offset columns with projectiles of the rimmed cartridges laterally spaced from a median plane by a first distance and rims of the rimmed cartridges laterally spaced from the median plane by a second distance that is greater than the first distance.
Example 25 includes the subject matter of any of Examples 1-24, where the magazine is configured for use with a handgun.
Example 26 includes the subject matter of any of Examples 1-25, where the magazine is configured for rimfire ammunition.
The foregoing description of example embodiments has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the present disclosure to the precise forms disclosed. Many modifications and variations are possible in light of this disclosure. It is intended that the scope of the present disclosure be limited not by this detailed description, but rather by the claims appended hereto. Future-filed applications claiming priority to this application may claim the disclosed subject matter in a different manner and generally may include any set of one or more limitations as variously disclosed or otherwise demonstrated herein.