The present invention generally relates to slide or pump action firearms, and more particularly to pump action mechanisms and associated bolt slide locks for such firearms.
Conventional AR-type rifles fire from a closed locked breech in which the bolt is locked in axial position to the receiver or barrel assembly before firing. The bolt carrier or slide that carries the bolt, however, is free to move axially to a certain degree. Normally, the recoil spring holds the breech closed, but on a pump action firearm, the bolt carrier is rigidly coupled with a slideable pump handle of some type mounted on the stock forend which is used to cycle the action. The forces of grasping the pump handle can often pull the bolt out of battery unintentionally and cause an operating malfunction. A lock for the bolt carrier is needed for pump action rifles to prevent this situation. The lock mechanism needs to be active until firing, at which point the lock must release the bolt carrier to manually cycle the action for extracting and ejecting the spent shell casing, and chambering a new round from the magazine. A manual release of some type is also needed to manually unload the chamber. Previous slide locks are sometimes mounted in the lower receiver of an AR-type rifle along with the trigger-operated firing mechanism, which can complicate construction and assembly of the firearm.
Improvements in pump action mechanisms and associated bolt slide locks is desired.
Embodiments of the present invention provide a slide lock mechanism for a manually-operated pump action of a firearm and method for operating the same. The firearm may be an AR-type rifle including a separate upper receiver and a lower receiver which may be pivotably mounted to the upper receiver in typical AR fashion. The present slide lock may be operably disposed in the upper receiver, thereby advantageously conserving precious space in the lower receiver for mounting the trigger-operated firing mechanism and ammunition feed related components including the trigger and magazine assemblies. This also provides a mechanically simpler and efficient arrangement of firearm components that is easy to assemble and disassemble for maintenance.
In one embodiment, the slide lock mechanism may be pivotably mounted on the bolt slide and cooperates with an interference surface on the upper receiver for locking the slide in a forward closed breech position. The bolt slide lock may further be arranged to cooperate and interface with the spring-biased hammer of the firing mechanism for automatically unlocking the slide lock after firing, thereby allowing the slide to cycle rearward under recoil when discharging the firearm to open the breech for extracting/ejecting a spent cartridge casing and chambering a new round in the barrel. The slide lock according to the present disclosure may further be configured to allow manual operation by a user to unlock the slide for opening the breech and removing a cartridge from the chamber of the barrel. To that end, a manual slide lock actuator pivotably mounted the receiver about a separate pivot pin/axis than the slide lock is provided which acts directly on the slide lock as further described herein.
The present disclosure further provides a pump mechanism for manually cycling the bolt slide between the forward closed breech and the rearward open breech position. The pump mechanism advantageously does not require coupling of a movable component directly to the barrel for operating the bolt slide. Instead, the pump mechanism includes a specially configured interface with the handguard which slideably couples a pump handle to the handguard, and in turn to the slide via a mechanical linkage as further described herein.
In one aspect, a pump action firearm with bolt slide locking mechanism comprises: a longitudinal axis; a receiver defining a longitudinal cavity; a barrel assembly coupled to the receiver; a bolt slide slideably disposed in the longitudinal cavity of the receiver, the bolt slide movable between a rearward open breech position and a forward closed breech position in battery with the barrel assembly; and a slide lock pivotably mounted to the bolt slide about a pivot axis and selectively engageable with an interference surface on the receiver, the slide lock pivotably movable between a locked position engaging the interference surface to prevent the slide from moving out of the closed breech position, and an unlocked position disengaging the interference surface to allow the slide to move out of the closed breech position to the open breech position.
In another aspect, a pump action firearm with bolt slide lock mechanism comprises: a longitudinal axis; a receiver comprising a trigger-actuated firing mechanism including a rotatable hammer movable along a firing axis between a rear cocked position and a forward firing position; a barrel assembly coupled to the receiver; a pump handle slideably disposed about the barrel assembly; a bolt slide slideably disposed in the receiver, the bolt slide coupled to the pump handle and movable between a rearward open breech position and a forward closed breech position in battery with the barrel assembly via moving the pump handle; a slide lock pivotably mounted to the bolt slide about a pivot axis laterally offset from the firing axis of the hammer; the slide lock comprising a laterally elongated body including an operating end selectively engageable with an interference surface of the receiver, and an opposite actuation end arranged to engage the hammer; wherein the slide lock is pivotably movable between a locked position in which the operating end engages the interference surface to prevent the slide from moving out of the closed breech position, and an unlocked position disengaging the interference surface to allow the slide to move out of the closed breech position to the open breech position.
According to another aspect, a method for operating an action of a firearm is provided. The method comprises: providing a firearm comprising a longitudinal axis, a receiver, a barrel assembly coupled to the receiver, a hammer pivotably mounted in the receiver, a bolt slide slideably disposed in the receiver for movement between a rearward open breech position and a forward closed breech position in battery with the barrel assembly, and a slide lock pivotably mounted to the bolt slide about a pivot axis; engaging an interference surface arranged on the receiver with the slide lock to hold the bolt slide in the closed breech position; releasing the hammer from a rear cocked position to a forward firing position along a firing axis; striking the slide lock with the hammer to rotate the slide lock about its pivot axis; disengaging the slide lock from the interference surface of the receiver; and moving the bolt slide rearward to the open breech position. In one embodiment, the pivot axis of the slide lock is laterally offset from the firing axis of the hammer. The step of moving the bolt slide rearward may include manually moving a pump handle on the firearm coupled to the bolt slide rearward to open the breech.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
The features of the preferred embodiments will be described with reference to the following drawings where like elements are labeled similarly, and in which:
All drawings are schematic and not necessarily to scale.
The features and benefits of the invention are illustrated and described herein by reference to exemplary (“example”) embodiments. This description of exemplary embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description. Accordingly, the disclosure expressly should not be limited to such exemplary embodiments illustrating some possible non-limiting combination of features that may exist alone or in other combinations of features.
In the description of embodiments disclosed herein, any reference to direction or orientation is merely intended for convenience of description and is not intended in any way to limit the scope of the present invention. Relative terms such as “lower,” “upper,” “horizontal,” “vertical,”, “above,” “below,” “up,” “down,” “top” and “bottom” as well as derivative thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description only and do not require that the apparatus be constructed or operated in a particular orientation. Terms such as “attached,” “affixed,” “connected,” “coupled,” “interconnected,” and similar refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise.
As used throughout, any ranges disclosed herein are used as shorthand for describing each and every value that is within the range. Any value within the range can be selected as the terminus of the range.
General reference is made in the discussion which follows to all of the figures. Figures particularly applicable to the particular discussion at hand in some instances will be pointed out for reference, but are not limiting as other figures may show the same features.
The firearm 20 generally includes a receiver 21 comprising an upper receiver 21-1, lower receiver 21-2 removably and pivotably coupled to the upper receiver by a transversely oriented front pivot pin 22 at a forward end, and a barrel assembly coupled to the upper receiver. This allows the lower receiver 21-2 to be hingedly opened to access the trigger and firing mechanism components housed in the lower receiver without uncoupling the lower receiver from the upper receiver. A transversely oriented second rear pin 23 at a rear end of the upper and lower receivers completes the coupling of the two receiver sections in typical AR-rifle fashion when fully assembled.
The lower receiver 21-2 primarily houses the trigger-operated firing mechanism and defines a magazine well 21-3 configured for removably receiving and retaining an ammunition magazine (not shown) in a conventional manner. The upper receiver 21-1 primarily houses the bolt slide 40 and ancillary components.
Further provided is a stock 24 attached to a rear end of the upper receiver 21-1 and a longitudinally-extending tubular handguard 25 extending forward from the front end of the upper receiver. Handguard 25 may be formed of a single one-piece monolithic unitary structure or multiple parts assembled together such as via fasteners. The stock 24 may be attached to the upper receiver via a conventional arrangement including a buffer tube 24-1 optionally containing an axially acting buffer or recoil spring 24-2 inside (see, e.g.
The barrel assembly includes a barrel 30 that defines a longitudinal axis LA of the firearm, a front muzzle end 30-1, and an opposite rear breech end 30-2 further defining a rearwardly open chamber 31 configured for holding an ammunition cartridge. A longitudinally-extending bore 43 is defined between ends 30-1, 30-2 which forms a passageway for a bullet, slug, or shot. The centerline of the barrel bore is coaxial with the longitudinal axis. The bore 43 may be rifled in some embodiments. An openable and closeable breech area (or simply “breech”) is defined at the rear breech end 30-2 of the barrel 30. The elongated bolt 51 carried by the bolt slide further described below includes a forward facing breech face 39 which creates a closed breech when in battery with the rear breech end 30-2 of the barrel for firing the firearm, or alternatively an open breech for extracting/ejecting spent cartridge casings and loading fresh cartridges into the chamber. Such operation is well known in the art without further elaboration. In one embodiment, a barrel extension 32 may be mounted on the rear breech end of the barrel that defines a plurality of inwardly extending radial bolt locking lugs 54 for forming a locked breech with radial bolt lugs 53 on the head of the bolt, as further described herein. The barrel extension 32 may be threadably coupled to the breech end of the barrel 30 in one implementation.
Referring to
The bolt slide and pump mechanism will now be further described.
The bolt head 52 protrudes axially forward from the front end of the bolt slide 40 and defines a vertical breech or bolt face 39 which abuts a chambered cartridge for support during firing (see, e.g.
The present firearm being described has a pump action mechanism configured to allow a user to manually cycle the bolt slide/bolt between the forward open breech and rearward closed breech positions. In one embodiment, the pump action mechanism 200 generally includes an externally mounted pump handle 202 and a mechanical linkage such as at least one operating rod 210 coupled between both the handle and bolt slide 40.
Referring generally to
The pump handle 202 may have a partial cylindrical configuration formed by the bottom wall 203 and the adjoining pair of arcuately curved circumferentially-extending sidewalls 201. Sidewalls 201 define an open top longitudinal channel 204 for receiving an upwardly protruding and longitudinally-extending top accessory rail 60 on the top 64 of the handguard 25 therein (see e.g.
The top accessory rail 60 may be configured as a section of a dovetail-shaped Picatinny rail or other type rail used in the art for mounting various accessories thereon such as laser or non-laser top sights. The handguard 25 may generally have a tubular substantially octagon shape in transverse cross section in one non-limiting embodiment; however, other cross-sectional shapes may be used such as circular. The handguard 25 may be a one-piece monolithic unitary structure or may be formed by an assembly of several parts fastened together. Handguard 25 has an axially elongated body including an open front end 61, open rear end 62, bottom 63, top 64, and circumferential sidewall 67 encircling the barrel of the firearm. The handguard 25 may include a downwardly protruding and laterally openable/closeable split clamp 68 which cooperates with a pair of transversely oriented threaded fasteners 69 (see, e.g.
The operating rod 210 may be cylindrical in configuration and is operably disposed inside the handguard 25. In one embodiment, the operating rod may be movably disposed in a longitudinally-extending passageway 65 formed in the upwardly protruding top accessory rail 60 of the handguard, as best shown in
The operating rod 210 extends outwards and rearwardly from the longitudinal passageway 65 beyond the rear end 62 of handguard for coupling to the bolt slide 40. The rear end of the operating rod 210 may be fixedly coupled to the bolt slide by a key block 70 mounted thereon in one embodiment. The key block 70 may be mounted on the top of the bolt slide 40, and in a position forward of the hammer slot 41 in one example arrangement (see, e.g.
The portions of the operating rod 210 forward of key block 70 may be coupled to the pump handle 202 via a yoke 220 supported by and slideably mounted to the handguard 25. At least one yoke 220, but preferably two yokes are provided for stabilizing the linear forward/rearward motion of the operating rod 210. The yoke 220 may have a generally T-shaped body which is inverted when mounted to the firearm as best shown in
The operating rod 210 may be fixedly/rigidly affixed to the yoke 220 in any suitable manner, such as for example without limitation pins or threaded fasteners. In one embodiment, the yoke 220 is cross-pinned to operating rod 210 by a cross pin 210-1 (see, e.g.
Each lateral support arm 221 of the yoke 220 is configured and arranged for coupling to the external pump handle 202 through the handguard 25. In one embodiment, the handguard includes two axially extending longitudinal travel slots 66 formed on opposite sides of the handguard which each receive one of the support arms therethrough. Support arms 221 extend outward completely through the handguard from the interior of the handguard through the longitudinal travel slots 66 and beyond the exterior surface of the handguard as shown for coupling directly to the pump handle external to the handguard. The support arms 221 slideably engage the travel slots 66 when the action is manually cycled rearward and forward by the user. Travel slots 66 extend axially for at least a distance of the handguard 25 commensurate with the length of travel of the pump handle 202 along the handguard when the action is cycled. The front and rear ends of the slots 66 are spaced inwards from the front and rear ends 61, 62 of the handguard 25.
In one embodiment, referring to
The yoke 220 in turn may be supported by handguard 25 alone, or alternatively by both the handguard and the top of the barrel 30 in one embodiment. A bottom surface of the yoke may include an arcuate and downwardly open concave recess 226 configured to slideably engage a corresponding top convex surface of the barrel 30 for rearward/forward movement thereon (see, e.g.
In operation, starting with a closed and locked breech, pulling the pump handle 202 rearward pushes and slides the bolt slide 40 rearward simultaneously with the handle via the operating rod 210 linkage. The bolt head 52 rotates and unlocks from the barrel locking lugs 54 via the cam pin 33 and slot 34 interaction as previously described herein to unlock the breech. The assembly of the operating rod 210, yokes 220 mounted thereon, and bolt slide 40 are all operably and rigidly linked together to travel rearward in unison while the barrel 30, receiver 21, and handguard 25 remain stationary to open the breech. The support arms 221 of the yokes 221 slide each along and within their respective longitudinal slots 66 in the handguard 25 along with the pump handle 202. It bears noting that the dual set of yoke arms 221 provide two sliding points of engagement with the handguard, thereby maintaining a stable rotational position of the operating rod 210 that prevents twisting. This advantageously ensures smooth sliding movement and travel of the assembly both rearward and forward. As the bolt slide 40 moves rearward, the spent cartridge casing is extracted from the barrel chamber 31 and ejected through the ejection port 130 on the right side of the upper receiver 21-1. The extractor mounted on the bolt and ejector are now shown. When the user moves the pump handle 202 and slide 40 concomitantly forward assisted by the buffer or return spring 24-2 which has been compressed by opening the breech, a new cartridge is uploaded into the breech area from the stack of spring-biased cartridges in the box style magazine mounted in the magazine well 21-3 of the lower receiver 21-2. As the bolt slide 40 continues forward, the new cartridge is stripped from the magazine by the bolt 51 and chambered. The breech is reclosed and re-locked for firing the next round.
The slide lock mechanism of the firearm 20 will now be described in further detail with general reference to
The slide lock 100 is pivotably movable in a horizontal plane about a vertical axis of rotation between a locked position preventing the bolt slide from being moved rearward, and unlocked position allowing the bolt slide to be manually move rearward by the user using the pump handle.
Referring to
The lateral section 101 of slide lock 100 includes a forwardly open spring slot 109 which receives a biasing spring 110 for biasing the slide lock into a locked position (see also
In one configuration, the pivot pin 105 of the slide lock 100 is laterally offset to the right of the hammer 28 and its travel path or line of action (i.e. firing axis F) as best shown in
With continuing reference to
Although the interference surface 108 may be conveniently formed on the ejection port 130 in the depicted embodiment to avoid having to create a separate surface for this purpose, the interference surface may alternatively be formed on any other forward facing surface that might be provided. Accordingly, the interference surface need not necessarily be associated with the ejection port. The invention is expressly not limited to utilizing the ejection port for the interference surface.
The longitudinal section 102 and right operating end 104 of slide lock 100 further includes a laterally outward facing push surface 116 which enables a user to manually unlock the slide lock 100 for unloading a chambered round of ammunition without firing the firearm. Push surface 116 is positioned rearward of the locking surfaces 115 on longitudinal section 102 and arranged for engagement by manual actuator 120 slideably mounted on the right lateral side of upper receiver 21-1, as further described herein. Push surface 116 additionally provides a rotational travel stop feature. Push surface 116 engages a laterally inward facing stop surface 116-1 formed on the upper receiver 21-1 which acts as a travel stop to limit the counter-clockwise rotation of slide lock 100 under the biasing action influence of operating spring 110 (see, e.g.
A method for operating the slide lock 40 will now be briefly described in the context or scenario of discharging the firearm via a trigger pull in which the slide lock is automatically moved between the locked and unlocked positions via operation of the hammer. When the firearm is in the ready-to-fire position, the bolt slide 40 is in battery with the rear breech end of the barrel 30 and the breech is closed and locked via engagement between the bolt lugs 53 and locking lugs 54 on the barrel extension 32. The slide lock is in the locked position. In one embodiment, the right operating end 104 of the slide lock 40 may be positioned slightly forward of the left actuation end 103 as shown in
When the trigger 27 is pulled by the user, the catch protrusion 55-2 of trigger 27 disengages the hammer trigger notch 55-1 and releases the hammer which rotates forward thereby striking both the firing pin 50 to detonate the chambered cartridge and the slide lock 100. The rearward facing actuation surface 111 of slide lock is forcibly contacted by the forward facing contact surface 112 of the hammer 28 as it rotates forward about its pivot axis (i.e. pivot pin 113. The slide lock 100 rotates about its pivot axis (i.e. pivot pin 105) to the unlocked position, thereby disengaging the stepped shoulder (i.e. locking surface 115) on the slide lock from the interference surface 108 in the ejection port 130 as the stepped shoulder and right operating end 104 of the slide lock rotates inwards. The breech may now be opened to extract and eject the spent cartridge casing by pulling the pump handle 202 rearward as previously described herein. The hammer 28 is rotated rearward and reset to the cocked position by engagement with the slide when it is drawn rearward in the upper receiver 21-1. When the bolt slide 40 is returned forward and the breech closes, the slide lock 100 re-engages the interference surface 108 on the upper receiver to resume the initial locked position in preparation for the next shot.
According to another aspect, the pump action firearm may further include a manual slide lock release mechanism comprising a depressible manual actuator 120 that operably cooperates and interfaces with the slide lock for manually unlocking the slide. This allows the breech to be opened by the user for removing a chambered cartridge or manually loading a cartridge into the chamber of the barrel. Referring generally to
The actuation end 121 of actuator 120 may be configured as an oblong button accessible to the user for depressing the actuator 120 inwards to activate the slide lock 100. Actuation end 121 may have a flat body with opposing internal and external major surfaces. The working end 122 may have a extends perpendicularly from the actuation end button and may have an elongated generally cylindrical body. Working end 122 may be terminated with a flat actuation flange 122-1 extending axially from its cylindrical body (see, e.g.
The actuator 120 is slideably and laterally (transversely) moveable between an outward deactivated position and an inward activated position. The operating spring 124 biases the actuator outwards towards the deactivated position.
In operation, depressing the actuator 120 inwards engages the working end 122 with the push surface 116 of the right longitudinal section 102 of the slide lock 100. This creates an inwardly directed thrust or pushing force on the operating end 104 of slide lock 100 which rotates the slide lock 100 from the locked position to the unlocked position about pivot pin 105, thereby disengaging the slide lock from the interference surface 108 of the receiver at the ejection port 130, as previously described herein. While continuing to hold the actuator inwards, the pump handle may be manually retracted by the user to open the breech for access to the barrel chamber (to remove a cartridge or hand-load a fresh cartridge into the chamber). When the actuator 120 is released by the user, the operating spring 124 automatically returns the actuator to the outward deactivated position.
It will be appreciated that any of the embodiments and features of the present invention disclosed herein may be used in various combinations with any of the other embodiments and features in various implementations of the invention.
While the foregoing description and drawings represent preferred or exemplary embodiments of the present invention, it will be understood that various additions, modifications and substitutions may be made therein without departing from the spirit and scope and range of equivalents of the accompanying claims. In particular, it will be clear to those skilled in the art that the present invention may be embodied in other forms, structures, arrangements, proportions, sizes, and with other elements, materials, and components, without departing from the spirit or essential characteristics thereof. In addition, numerous variations in the methods/processes as applicable described herein may be made without departing from the spirit of the invention. One skilled in the art will further appreciate that the invention may be used with many modifications of structure, arrangement, proportions, sizes, materials, and components and otherwise, used in the practice of the invention, which are particularly adapted to specific environments and operative requirements without departing from the principles of the present invention. The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being defined by the appended claims and equivalents thereof, and not limited to the foregoing description or embodiments. Rather, the appended claims should be construed broadly, to include other variants and embodiments of the invention, which may be made by those skilled in the art without departing from the scope and range of equivalents of the invention.
The present application claims of the benefit of U.S. Provisional Application No. 62/615,100 filed Jan. 9, 2018; the entirety of which is incorporated herein by reference.
Number | Date | Country | |
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62615100 | Jan 2018 | US |