Bolt action is a type of firearm action where the handling of cartridges into and out of the firearm's barrel chamber is operated by manually manipulating a bolt directly via a handle. When the handle is operated, the bolt is unlocked from the receiver and pulled back to open the breech, allowing the spent cartridge case to be extracted and ejected, the firing pin within the bolt is cocked either on opening or closing of the bolt depending on the gun design, and engages the sear. Then upon the bolt being pushed back a new cartridge is loaded into the chamber. Finally, the breech is closed tight by the bolt locking against the receiver.
Bolt-action firearms are most often rifles, but there are some bolt-action variants of shotguns and a few handguns as well. Examples of this system date as far back as the early 19th century. From the late 19th century, all the way through both World Wars, the bolt-action rifle was the standard infantry firearm for most of the world's military forces. In modern military and law enforcement use, the bolt-action has been mostly replaced by semi-automatic and selective-fire firearms, though the bolt-action design remains popular in dedicated sniper rifles due to inherently more rugged design and are still very popular for civilian hunting and target shooting.
To couple or decouple the bolt from the firearm, a bolt release is provided. In some firearms, the trigger itself is configured to provide the bolt release. A problem with conventional triggers is that they often have a large over travel. Over travel is any amount of additional trigger movement following a trigger break point. Shooters may find a large over travel disruptive. Conventional solutions use set screws to limit trigger over travel. However, when the trigger is used as a bolt release, using set screw to inhibit over travel becomes very complex, if at all possible.
Accordingly, it is an object to provide a trigger device that obviates or mitigates at least some of these disadvantages.
In accordance with as aspect of an embodiment, there is provided a trigger device comprising: a housing; a trigger rotatably coupled in the housing via a trigger pivot pin, the trigger comprising a trigger stop arm; a bolt pin moveable between a bolt open position and a bolt closed position in response to positioning of a bolt, a bolt pin arm rotatably coupled proximal one end to the housing and at another end to the bolt pin, the bolt pin arm comprising an over travel stop configured to selectively engage with the trigger stop arm; wherein: in the bolt closed position, the over travel stop is positioned within a travel path of the trigger stop arm; and in the bolt open position, the over travel stop is positioned outside of the travel path of the trigger stop arm.
In an embodiment, a ticker is coupled to the trigger. The ticker comprises a cam surface and the bolt pin arm comprises a cam protrusion proximal the one end. The cam protrusion is configured to engage the cam surface. In the bolt open position, the trigger stop arm is configured to bypass the over travel stop, the ticker is configured to rotate the bolt pin arm by engagement of the cam surface with the cam protrusion, and the bolt pin arm is configured to move the bolt pin from the bolt open position to a bolt release position;
In an embodiment, the over travel stop is positioned to inhibit movement of the trigger immediately following a break to provide minimal over travel. Alternatively, the over travel stop is positioned to inhibit movement of the trigger at a point beyond a break to provide an acceptable amount over travel. The ticker is rotatably coupled with the trigger at a ticker pivot pin and configured to rotate about the ticker pivot pin when the trigger stop arm engages the over travel stop.
The trigger stop arm may comprise a trigger stop interface and the over travel stop may be configured to interface with trigger stop interface. The over travel stop may be adjustably coupled to the bolt pin arm to provide a variable over travel distance.
Embodiments of the description will now be described by way of example only with reference to the following drawings in which:
For convenience, like numerals in the description refer to like structures in the drawings. Referring to
The trigger 102 comprises an actuation member 120 and a trigger stop arm 122. The actuation member 120 comprises an arcuate portion 120a configured to interface with a user's finger and a main body 120b configured to rotate about a trigger pivot pin 160. The trigger stop arm 122 is coupled to the main body 120b at a distal end from the arcuate portion 120a. The trigger stop arm 122 comprises a trigger stop interface 122a at a distal end from the main body 120b. The trigger stop interface 122a is configured to selectively engage with the bolt pin arm 112. As the trigger 102 rotates about the trigger pivot pin 160, the trigger stop interface 122a travels in an arcuate path P.
The ticker 103 comprises a main portion 103a, a sear-engagement portion 103b, a trigger engagement portion 103c, and a ticker arm 103d. The main portion 103a is rotationally coupled to the trigger stop arm 122 about a ticker pivot pin 166. The sear engagement portion 103b and the trigger engagement portion 103c extend from the main portion 103a in opposing directions. The sear engagement portion 103b has a cam surface 103e configured to selectively engage with the bolt pin arm 112. The ticker arm 103d extends from the main portion 103a in a direction substantially perpendicular to the sear engagement portion 103b and the actuation member engagement portion 103c.
As will be described, as force is applied to the trigger actuation member 120, the trigger 102 and the ticker 103 rotate in unison about the trigger pivot pin 160. Once the trigger fires and the sear 108 is released, motion of the sear 108 will cause the ticker to rotate about the ticker pivot pin 166, while motion of the trigger 102 about the trigger pivot pin 160 is inhibited by the trigger stop arm 122.
The spring 104 is coupled between a distal end of the ticker arm 103d and the trigger pull-weight adjustment mechanism 106. When the sear 108 is engaged by the bolt of the bolt-action firearm, it is biased to rotate about a sear pivot pin 164. Conversely, the spring 104 is configured to bias the trigger 102 and the ticker 103 to rotate in an opposite direction about the trigger pivot pin 160. These forces bias the sear 108 and the sear engagement portion 103b of the ticker 103 to trap the roller 114 there between. The force required to overcome the bias of the spring 104 and release the sear 108 is the pull weight of the trigger device 100.
The trigger pull-weight adjustment mechanism 106 comprises a feedback member, and a threaded wedge screw. The feedback member comprises a plurality of wedge shaped projections spaced about its surface. A first end of the threaded wedge screw is generally shaped to be complementary to the wedge shaped projections on the feedback member. A second end of the threaded wedge screw comprises a socket configured to receive a tool. For example, the socket can be a hexagonal socket and the tool can be an Allen key, hex key, screwdriver, or the like. Movement of the pull-weight adjustment mechanism 106 causes the trigger biasing spring 104 to compress or expand, thereby modifying the pull-weight of the trigger device 100. The trigger pull-weight adjustment mechanism 106 is described in greater detail in U.S. Pat. No. 9,752,841.
The bolt pin arm 112 is rotationally coupled proximal a first end to a bolt pin arm pivot pin 162. The bolt pin arm 112 comprises a cam projection 112a proximal the first end. The cam projection 112a is shaped and configured to selectively interface with the cam surface 103e of the ticker 103. A second end 112b of the bolt pin arm 112, distal to the first end, is configured to be coupled with the bolt pin 110. The bolt pin arm 112 further comprises an over travel stop 112c configured to selectively engage with the trigger stop interface 122a. In an embodiment, the over travel stop 112c is a protrusion that extends laterally from the bolt pin arm 112.
The bolt pin 110 comprises a recess 110a configured to receive and engage the second end 112b of the bolt pin arm 112. Thus, moving the bolt pin 110 will correspondingly move the bolt pin arm 112, and vice versa. The bolt pin 110 is movable between a bolt open position, a bolt closed position, and a bolt release position. The bolt open position is the most extended position of the bolt pin 110. The bolt release position is the most contracted position of the bolt pin 110. In the bolt closed position, the bolt pin arm 112 is positioned so that the over travel stop 112c is within the travel path P of the trigger stop interface 122a. In the bolt open position, the bolt pin arm 112 is moved so that the over travel stop 112c is outside of the travel path P of the trigger stop interface 122a.
In the present embodiment, the bolt pin 110 is biased by a biasing member (not shown) in the bolt open position. When the trigger device 100 is assembled in a bolt-action firearm, closing the bolt engages the bolt pin 110 and moves it to the bolt closed position. When the bolt is in the bolt open position, the bolt pin 110 can be moved to the bolt release position by actuating the trigger 102 as will be described.
Referring to
As pressure is applied to the trigger actuation member 120, the trigger 102 and the ticker 103 rotate about the trigger pivot pin 160 and the sear engagement portion 103b of the ticker 103 begins to disengage from the sear 108, freeing the roller 114. Referring to
Although not visible in the figures, the surface of the sear 108 that interfaces with the roller 114 is sloped. Accordingly, as the sear 108 continues to release, a horizontal force continues to be applied to the ticker 103. Since the trigger 102 is inhibited from moving further by the over travel stop 112c, the ticker 103 begins to rotate about the ticker pivot pin 166, as shown in
As described above, in this embodiment the over travel stop 112c is positioned to provide little or no perceptible over travel of the trigger 102 after the break. However, some users may prefer some level of over travel. Accordingly, in an alternative embodiment, the over travel stop is positioned to allow an acceptable amount of travel of the trigger past the break before the trigger stop interface 122a engages the over travel stop 112c. As will be appreciated, what is considered to be acceptable is subjective and can be determined upon design of the trigger device 100. In this embodiment, the ticker 103 may not need to rotate at all about the ticker pivot pin 166. This will depend on whether the over travel distance provides sufficient disengagement of the sear engagement portion 103a of the ticker from the sear 108 to allow the sear to completely release. In yet an alternate embodiment, the over travel stop 112c is adjustably positioned on the bolt pin arm 112. Preferably, adjustability of the over travel stop 112c may be limited at one end so that it cannot be positioned to prevent the trigger 102 from firing the trigger device 100. Further, the adjustability of the over travel stop 112c may be limited the other end to provide a maximum over travel amount.
Referring to
Further movement of the trigger 102 causes the cam surface 103e to slidingly engage the cam projection 112a. Engagement of the cam surface 103e with the cam projection 112a causes the bolt pin arm 112 to rotate about the bolt pin arm pivot pin 162. Rotation of the bolt pin arm 112 causes the bolt pin 110 to contract toward the bolt release position. Referring to
Accordingly, it will be appreciated that the invention described herein provides a trigger device, that that is used to release a bolt assembly from a firearm, with an over travel stop. Although the description has been made with reference to specific embodiments, those skilled in the art will appreciate that modifications can be made thereto. Thus, the scope of the claims should not be limited by the preferred embodiments set forth in the examples but should be given the broadest interpretation consistent with the description as a whole.
The present application relates generally to a trigger device for a bolt-action firearm, and specifically to a trigger device configured to provide a trigger over travel stop in a bolt-action firearm. This application claims priority to U.S. Provisional Application No. 62/876,237 filed Jul. 19, 2019 and titled “Trigger Device with Over Travel Stop,” the contents of which are incorporated herein by reference.
Number | Date | Country | |
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62876237 | Jul 2019 | US |