Ejector for firearm

An ejector mechanism for a firearm includes an ejector disposed at a forward face of a bolt. The ejector includes a hole designed to provide clearance for the firing pin to pass at least partially through the ejector. The hole may include a counterbore on a rear side of the ejector.

FIELD OF THE INVENTION

The field of the invention relates to firearms, particularly ejector mechanisms for ejecting a shell or cartridge from the firearm during manual or automated (semi-automatic or automatic) operation of the firearm.

BACKGROUND

Many modern firearms (including handguns, rifles, carbines, shotguns, etc.) rely on at least one of an extractor mechanism and an ejector mechanism for expelling a cartridge or cartridge case from the firearm when the bolt moves away from the chamber. The ejector mechanism may be based on a mechanical operation and/or may be operated by a spring. In addition, the ejector mechanism may be located or attached to a lower receiver, an upper receiver, a bolt, or any other relevant portion of the firearm. Many firearms and related accessories are designed for compatibility with the AR-15 variant (civilian) or M16/M4 (military) firearm platform (i.e., collectively, AR-15 style firearms). Many of these products follow traditional designs based on industry standards and/or military specification (milspec).

To simplify the firearm operating system, to increase reliability, and to increase consistency of the ejection pattern for cartridges or cartridge cases exiting the firearm, it may be desirable to design a new ejection mechanism located near the center of the bolt face.

SUMMARY

According to certain embodiments of the present invention, an ejector mechanism for a firearm comprises: an ejector disposed at a forward face of a bolt, wherein the ejector comprises a hole designed to provide clearance for the firing pin to pass at least partially through the ejector.

According to certain embodiments of the present invention, an ejector mechanism for a firearm comprises: an ejector disposed at a forward face of a bolt, wherein at least a portion of the ejector is disposed at a center of the forward face of the bolt.

DETAILED DESCRIPTION

Although the illustrated embodiments inFIGS.1A-11Bshow components of various semi-automatic or automatic firearms, the features, concepts, and functions described herein are also applicable (with potential necessary alterations for particular applications) to handguns, rifles, carbines, shotguns, or any other type of firearm, including firearms that operate manually (e.g., bolt action, lever action, or other relevant firearms). Furthermore, the embodiments may be compatible with various calibers including rifle calibers such as, for example, 5.56×45 mm NATO, 0.223 Remington, 7.62×51 mm NATO, .308 Winchester, 7.62×39 mm, 5.45×39 mm; pistol calibers such as, for example, 9×19 mm, 0.45 ACP, 0.40 S&W, 0.380 ACP, 10 mm Auto, 5.7×28 mm, .22 Long Rifle; and shotgun calibers such as, for example, 12 gauge, 20 gauge, 28 gauge, 0.410 gauge, 10 gauge, 16 gauge. The illustrated embodiments focus on an upper receiver for the AR-15 variant (civilian) or M16/M4 (military) firearm platform (i.e., AR-15 style firearms); however, the concepts and features described herein can be are also applicable (with potential necessary alterations for particular applications) to other components of AR-15 style firearms and to components of other firearms.

In some cases, a firearm1includes a firearm operating system3000, an upper receiver30, and a barrel50(seeFIG.1). Other components, including, for example, a charging handle, a buffer tube, a lower receiver, a fire control group, a stock, a grip, a magazine, and a handguard, are not illustrated for simplicity.

According to certain embodiments of the present invention, as shown inFIGS.1-10, a firearm operating system3000may include a bolt3020, an ejector mechanism100, an extractor mechanism200, and a barrel extension3060. In some cases, the firearm operating system3000is located within the upper receiver30. The firearm operating system3000may be designed as an assembly of components to fit within a standard upper receiver (e.g., upper receiver30shown transparent inFIG.1) for a known modular firearm such that the upper receiver30(including the firearm operating system3000) can interface with a standard lower receiver. For example, the firearm operating system3000may be designed to function and engage with (i) components of AR-15 variant (civilian) or M16/M4 (military) firearms; (ii) components of AR-10 variant firearms; or (iii) components of any other relevant firearm.

As shown inFIGS.2,3, and5, in some cases, the overall shape of the bolt3020includes a forward portion3104and a rear portion3106. The forward portion3104includes non-circular profile with at least one flat lateral portion connected by a curved upper portion and an approximately rectangular lower portion3108. The rear portion3106may be approximately cylindrical.

The ejector mechanism100may include an ejector101, a spring120, and a retaining pin3117(seeFIG.3). The extractor mechanism200may include an extractor201, an extractor plunger203, and a spring220.

In some embodiments, the ejector101interfaces with the ejector cavity3101of the bolt3020. As shown inFIGS.3-6B, in some embodiments, the ejector101includes a forward interface102, a rear protrusion105, and a hole107. The forward interface102may include the entire front facing surface of the ejector101and/or may protrude forward relative to the other portions of the ejector101such that the forward interface102is the only portion of the ejector101that contacts a cartridge disposed adjacent to a forward side of the bolt3020(e.g., seeFIGS.10-11B). In some examples, as shown inFIG.11A, the forward interface102includes a contact surface102athat protrudes forward and a secondary surface102bthat is offset rearward from the contact surface102a. The rear protrusion105of the ejector101may extend into a corresponding hole3111of the bolt3020and interface with a spring (e.g., spring120) within the hole3111.FIGS.2,3, and10show examples where the hole3111of the bolt3020is located at the 6 o'clock (bottom) position when viewing the forward face3103of the bolt3020.FIG.9shows another example where the hole3111of the bolt3020is located at the 4 o'clock position (and/or at a location that is 180° from the extractor201) when viewing the forward face3103of the bolt3020.

The ejector101may be designed to include a portion that extends away from the location of the hole3111on the forward face3103. For example,FIG.10shows an example where the ejector101extends around the perimeter of the forward face3103and locates the forward interface102on the perimeter of the forward face3103at a position that is approximately 180° from the extractor201(at a maximum distance from the extractor201). Such a configuration provides the longest possible moment arm for the ejector101relative to the pivot point created by the extractor201. However, such a configuration maximizes the necessary travel or necessary displacement for the ejector101. In addition, during rearward travel of the bolt3020after exiting the chamber, the cartridge (or an empty shell of a cartridge if a round was fired) may not be sitting flat against the forward face3103because the forward end of the cartridge/shell may be pushed against the inner surface of the barrel extension3060. For example, the ejector101may push the cartridge/shell and the cartridge/shell may pivot relative to the extractor201. When the cartridge/shell is angled relative to the forward face3103(as described above), some of the travel length of the ejector is depleted. This depletion can be affected in two ways. First, shorter cartridges/shells (such as handgun caliber) can pivot more, which depletes more travel of the ejector101. Second, a longer relative distance of the ejector from the extractor creates more room for the ejector to travel before the bolt3020reaches the ejection port31of the upper receiver30. As described in more detail below, ejection can be improved by shortening the length between the ejector101and the extractor201, assuming that the strength of the spring120is sufficient to overcome the shorter moment arm.

As shown inFIGS.2,3, and7, to improve ejection strength, reliability, and repeatability, the ejector101may be designed to extend toward the center of the forward face3103, which reduces the length between the ejector101and the extractor201. The ejector101may be designed to extend to or adjacent to a portion of the forward face3103through which the firing pin3080extends. In some embodiments, the ejector101extends to the portion of the forward face3103and includes a hole103for the firing pin3080. The hole103may include a counterbore108to provide sufficient clearance for the firing pin3080.

Accordingly, the ejector101may be designed such that the rear protrusion105extends rearward at the 6 o'clock position when viewing the forward face3103of the bolt3020. To install the ejector101into the bolt3020, a spring120is inserted into hole3111such that the opposite end of the spring120will bottom out in cavity106(or against rear surface109), which will compress when the ejector101is pushed rearward. After inserting the ejector101into the ejector cavity3101, the ejector101is adjusted such that the hole107is aligned with a portion of hole3115(between forward end3115.1and rear end3115.2) of the bolt3020and a retaining pin3117is then inserted into hole3115and hole107. The retaining pin3117may be a roll pin, a solid pin, or any other appropriate configuration used to retain the ejector101. The ejector spring120is compressed within hole3111when the ejector101is pushed rearward. For example, when a rim of a cartridge is retained by extractor201, the rear surface of the cartridge presses the ejector101rearward such that the forward interface102is approximately flush with a rear wall or floor of the forward cavity3028. In some embodiments, when the forward interface102is approximately flush with the rear wall of the forward cavity3028, the rear end3115.2of hole3115is adjacent to or in contact with retaining pin3117. When the bolt3020moves rearward due to either (i) manual operation/movement (e.g., operating the charging handle) or (ii) cycling of the firearm1after firing a cartridge, the spring in hole3111pushes the ejector101forward such that once the forward face3103reaches the ejection port31of the upper receiver30, the ejector101pushes the rear surface of a cartridge (or an empty shell of a cartridge if a round was fired) causing the cartridge/shell to pivot about the extractor201and exit the firearm1. The bolt3020may be configured with a smaller hole that extends through hole3111to the rear face3107of the bolt3020which allows the operator to push the ejector spring out of the hole3111from the rear.

The shape of the ejector101and the corresponding cavity3101of the bolt3020may be based on creating an offset from the location of the firing pin hole (central hole3027) through the bolt. In some embodiments, the cavity3101includes a flat wall and the ejector101includes a flat surface104designed to create a minimum offset from the extractor cavity3102(seeFIGS.4A and4B). As shown inFIGS.5A and5B, the ejector101may be designed for an ambidextrous system where the extractor201can be located on either side of the bolt3020and the ejector101has two flat surfaces104. Although the surface104is illustrated as flat/planar and parallel to the extractor cavity3102, the surface104may be a curved or otherwise nonplanar surface and/or may be nonparallel to the extractor cavity3102. In some embodiments, the shape or contour of the surface104is designed to affect or control the flight of the cartridge/shell being ejected.

In some embodiments, the size and/or shape of the ejector101near the firing pin hole103is designed to increase safety. For example, the portion of the ejector101in this area may be designed to be larger (or in some cases significantly larger) than the primer for the appropriate cartridge.

As illustrated inFIGS.6A and6B, the ejector101may be designed to only partially surround or enclose the firing pin hole103. For example, the ejector101may extend up from the hole3111and stop short of the central hole3027. In some embodiments, the ejector101includes a hole103that surrounds or encloses the bottom side of the central hole3027. In other embodiments, the ejector101includes a hole103that surrounds or encloses the right side of the central hole3027, along with portions of the bottom side and the top side (as shown inFIGS.6A and6B). In other embodiments, the ejector101includes a hole103that surrounds or encloses at least a portion of the left side of the central hole3027. The hole103may surround approximately half of the central hole3027. In other cases, the hole103may surround approximately 10%, 20%, 30%, 40%, 60%, 70%, 80%, 90% or any other appropriate portion of the central hole3027. In some embodiments, the entire ejector101is located at or near the center of the forward face3103of the bolt3020(i.e., there is no rear protrusion105).

As shown inFIGS.7-9, ejector101as described above can be adapted to function with an otherwise standard AR-15 style bolt carrier group. The rear protrusion105extends into hole3111, which is in a typical location for a standard AR-15 ejector. However, as shown inFIG.9, the bolt3020includes a cavity3101for the ejector101that is not typical for AR-15 bolt carrier groups. The ejector101shown inFIGS.7-8Bimproves the strength, reliability, and repeatability of the ejection for an AR-15 bolt carrier group.

The extractor201may be located within the extractor cavity3102of the bolt3020such that the extractor201can move based on the geometry of the cavity3102and an interface with an extractor plunger203inserted into extractor spring cavity3122. As shown inFIG.3, the extractor201may include a front surface207, a hook member204, and a rear member206. In some embodiments, the extractor201rotates and lip204engages the rim of a cartridge or empty shell. In some embodiments, as shown inFIG.3, the extractor201includes a protrusion205that locates and defines movement of the extractor201relative to the bolt3020(in coordination with the extractor plunger203as described below). The protrusion205may engage a corresponding recess within the extractor cavity3102(e.g., see cylindrical recess within extractor cavity3102inFIG.3). The hook member204of extractor201may be configured to engage a cannelure and/or a rim of the cartridge such that the extractor201guides the cartridge (or the empty shell of a cartridge if a round was fired) in the direction of the ejection port31of the upper receiver30using the force provided by the ejector101. In some embodiments, the extractor201includes at least one opening202that allows excess gas and carbon to escape from the cavity3102.

In some embodiments, rotation of the extractor201depends on an interface with the extractor plunger203. The extractor plunger203may include a rear portion203.4, a front portion203.3, a rear surface203.1, and a surface203.2. In some cases, the rear portion203.4may be cylindrical and the front portion203.3may include a blade shape having a flat portion and/or a rectangular cross section. A spring220may be inserted into hole3122. The extractor plunger203is then inserted into hole3122of the bolt3020and the spring220is compressed against the rear surface203.1such that the surface203.2is approximately aligned and/or continuous with profile surface3105of the bolt3020. In some embodiments, the front portion203.3presses against the rear member206of the extractor201to bias the extractor201toward engagement with a cartridge. The bolt3020may be configured with a smaller hole that extends through hole3122to the rear face3107of the bolt3020which allows the operator to push the extractor spring220out of the hole3122from the rear.

When the bolt3020moves forward over the top of a magazine, the lower portion3108pushes the upper-most cartridge out of the magazine and toward the barrel extension3060and the chamber of the firearm1. In some embodiments, the bolt3020may include a gap3108.1in the lower portion3108, which allows excess gas and carbon to escape from the forward cavity3028.

When the cartridge is in the chamber in a firing position, the cartridge is approximately aligned with a center of the forward face3103of the bolt3020such that the central hole3027of the bolt3020and/or the hole103of the ejector101are aligned with the primer of the cartridge (to align the forward end3081of the firing pin3080with the cartridge). When the cartridge is in the firing position, forward motion of the firing pin3080(e.g., caused by a hammer interacting with the rear end3083of the firing pin3080) causes the cartridge to discharge.

In some embodiments, as shown inFIGS.11A and11B, the ejector101may include a hole110between the firing pin hole103and the rear protrusion105. The hole110may provide heat transfer benefits such that less heat is transferred from the upper portion of the ejector101to the rear protrusion105(and the spring120). For example, the hole may provide additional surface area for convective heat transfer and may reduce the amount of material for conducting heat toward the spring120. In some cases, the hole110is a through hole extending through the ejector101while in other cases, the hole110is a blind hole.

The components of any of the firearms1described herein may be formed of materials including, but not limited to, thermoplastic, carbon composite, plastic, nylon, polyetherimide, steel, aluminum, stainless steel, high strength aluminum alloy, other plastic or polymer materials, other metallic materials, other composite materials, or other similar materials. Moreover, the components of the firearms may be attached to one another via suitable fasteners, which include, but are not limited to, screws, bolts, rivets, welds, co-molding, injection molding, or other mechanical or chemical fasteners.