Semiautomatic firearm

Abstract

A trigger assembly of a semi-automatic firearm including a hammer including a capture feature and a reset feature, a trigger including a sear portion releasably coupled to the hammer, a trigger spring configured to urge the trigger toward a battery position and adjustable to alter a spring force applied to the trigger, a disconnector including a forward edge configured to engage with the reset feature of the hammer, a hammer stop including a catch configured to, when the hammer stop is in a battery position, arrest the capture feature of the hammer when the hammer stop is in a battery position, and a reset spring coupled between the hammer stop and the disconnector such that the reset spring is configured to urge the disconnector toward a position to engage with the reset feature of the hammer.

Description

SEMIAUTOMATIC FIREARMCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This patent application claims the benefit of U.S. Provisional Application No. 63 / 610,273, entitled SEMIAUTOMATIC FIREARM, filed December 14, 2023, the contents of which are expressly incorporated by reference herein.TECHNICAL FIELD

[0002] The present disclosure is related to semiautomatic firearms, specifically semiautomatic rimfire firearms with improved trigger assembly and bolt design.BACKGROUND

[0003] Semi-automatic firearms have been widely used for sporting, hunting, and selfdefense purposes for many decades. These firearms typically utilize the energy from a fired cartridge to extract the spent casing, cock the hammer, and load a new cartridge into the chamber, allowing for rapid follow-up shots without manual cycling of the action.

[0004] Rimfire ammunition, characterized by its primer being contained within the rim of the cartridge base, has long been popular due to its relatively low cost and mild recoil. However, designing reliable semi-automatic actions for rimfire cartridges presents unique challenges. The lower pressures generated by rimfire ammunition compared to centerfire cartridges can make it difficult to ensure consistent cycling of the action.

[0005] Trigger mechanisms for semi-automatic firearms must balance safety, reliability, and user experience. Many designs struggle to provide an adjustable trigger pull weight while maintaining proper reset functionality and safety features. Additionally, the integration of passive safety mechanisms to prevent accidental discharge if the firearm is dropped or mishandled remains an important consideration.

[0006] The bolt and extractor design in semi-automatic rimfire firearms is critical for reliable feeding, firing, and ejection of cartridges. Proper headspacing, secure cartridge retention, and consistent primer strikes are essential for accuracy and dependable operation. However, existing designs may struggle with higher-pressure rimfire cartridges or fail to provide adequate case support, potentially leading to malfunctions or safety concerns.

[0007] As rimfire cartridge technology has advanced, new high-performance options have emerged that generate higher pressures and velocities than traditional rimfire ammunition. These cartridges present additional engineering challenges for semi-automatic actions originally designed for lower-pressure rounds. Adapting existing designs or creating new systems capable of reliably cycling these more powerful cartridges while maintainingsafety and accuracy is an ongoing area of development in the firearms industry.SUMMARY OF THE INVENTION

[0008] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0009] According to an aspect of the present disclosure, a trigger assembly of a semiautomatic firearm for firing rimfire ammunition is provided. The trigger assembly includes a hammer rotatable about a first axis, the hammer including a capture feature and a reset feature. The trigger assembly includes a trigger rotatable about a second axis, the trigger comprising a sear portion releasably coupled to the hammer. The trigger assembly includes a trigger spring configured to urge the trigger toward a battery position, wherein the trigger spring is adjustable to alter a spring force applied to the trigger. The trigger assembly includes a disconnector rotatable about the second axis, the disconnector comprising a forward edge configured to engage with the reset feature of the hammer. The trigger assembly includes a hammer stop rotatable about the second axis, the hammer stop comprising a catch configured to, when the hammer stop is in a battery position, arrest the capture feature of the hammer when the hammer stop is in a battery position. The trigger assembly includes a reset spring coupled between the hammer stop and the disconnector, wherein the reset spring is configured to urge the disconnector toward a position to engage with the reset feature of the hammer.

[0010] According to other aspects of the present disclosure, the trigger assembly may include one or more of the following features. The hammer stop may further comprise a reset spring portion configured to engage and support the reset spring. The hammer stop may comprise a safety trigger comprising a second finger hook having a portion extending forwardly of the first finger hook when the trigger assembly is in a battery position, and wherein, by rotation of the hammer stop, when the portion of the safety trigger is flush with the first finger hook portion, the catch of the hammer stop may be positioned to allow free rotation of the hammer. The forward edge of the disconnector may be configured to engage with the reset feature of the hammer when the hammer is driven backward by a bolt after firing. The hammer stop, when rotated from the battery position, may be configured to disengage the forward edge of the disconnector from the hammer. The hammer may define an elongate aperture configured to receive at least a portion of the catch of the hammer stoptherethrough. The hammer stop may comprise a planar component and the reset spring may comprise a compression spring.

[0011] According to another aspect of the present disclosure, a semi-automatic firearm for firing rimfire ammunition is provided. The semi-automatic firearm includes a barrel defining a chamber for receiving and firing a rimfire cartridge. The semi-automatic firearm includes a receiver operatively coupled to the barrel. The semi-automatic firearm includes a bolt assembly operatively coupled to the receiver and adapted for loading, firing, and ejecting the rimfire cartridge. The bolt assembly includes a bolt body with a forward bolt face. The bolt assembly includes a recess defined on the forward bolt face for receiving a head of a rimfire cartridge, the recess being proximally bound by a base surface on the bolt face. The bolt assembly includes a ledge portion that partially surrounds the base surface of the bolt face, the ledge portion including an inclined face configured to accept a rim portion of the rimfire cartridge. The bolt assembly includes a retractable extractor disposed proximate the recess. The bolt assembly includes a firing pin that selectively extends into the recess in a direction normal to the base surface, the firing pin being parallel to and non-concentric with a central axis of the bolt body. The semi-automatic firearm includes a trigger assembly. The trigger assembly includes a hammer rotatable about a first axis, the hammer including a capture feature and a reset feature. The trigger assembly includes a trigger rotatable about a second axis, the trigger comprising a sear portion releasably coupled to the hammer. The trigger assembly includes a trigger spring configured to urge the trigger toward a battery position. The trigger assembly includes a disconnector rotatable about the second axis, the disconnector comprising a forward edge configured to engage with the reset feature of the hammer. The trigger assembly includes a hammer stop rotatable about the second axis, the hammer stop comprising a catch configured to, when the hammer stop is in a battery position, arrest the capture feature of the hammer. The trigger assembly includes a reset spring coupled between the hammer stop and the disconnector, wherein the reset spring is configured to urge the disconnector toward a position to engage with the reset feature of the hammer.

[0012] According to other aspects of the present disclosure, the semi-automatic firearm may include one or more of the following features. The retractable extractor may comprise a bias portion configured to displace the extractor to receive a push fed rimfire cartridge. The firing pin may comprise a spherical tip. The recess defined by the forward bolt face may be substantially spherical. A diameter of the recess may be less than about 10 percent greater than a diameter of the spherical tip of the firing pin. The ledge portion may include an arcuate segment that partially surrounds the base surface of the bolt face, the arcuate segmentdefining a radius about the central axis. The retractable extractor may be substantially centered at a location diametrically opposed to a junction point of a straight portion and the arcuate segment of the ledge portion.

[0013] According to another aspect of the present disclosure, a trigger assembly for a semi-automatic firearm for firing rimfire ammunition is provided. The trigger assembly includes a hammer rotatable about a first axis, the hammer including a capture feature and a reset feature. The trigger assembly includes a trigger rotatable about a second axis, the trigger comprising a sear portion releasably coupled to the hammer. The trigger assembly includes a trigger spring configured to urge the trigger toward a battery position. The trigger assembly includes a disconnector rotatable about the second axis, the disconnector comprising a forward edge configured to engage with the reset feature of the hammer. The trigger assembly includes a hammer stop rotatable about the second axis, the hammer stop comprising a catch configured to, when the hammer stop is in a battery position, arrest the capture feature of the hammer. The trigger assembly includes a reset spring coupled between the hammer stop and the disconnector, wherein the reset spring is configured to urge the disconnector toward a position to engage with the reset feature of the hammer.

[0014] According to other aspects of the present disclosure, the trigger assembly may include one or more of the following features. The hammer stop may further comprise a reset spring portion configured to engage and support the reset spring. The hammer stop may comprise a safety trigger having a portion extending forwardly of a finger hook of the trigger when the trigger assembly is in a battery position, and wherein, by rotation of the hammer stop, when the portion of the safety trigger is flush with the finger hook portion, the catch of the hammer stop may be positioned to allow rotation of the hammer. The forward edge of the disconnector may be configured to engage with the reset feature of the hammer when the hammer is driven backward after firing. The hammer stop, when rotated from the battery position, may be configured to disengage the forward edge of the disconnector from the hammer. The hammer may define an aperture configured to receive at least a portion of the catch of the hammer stop therethrough.

[0015] The foregoing general description of the illustrative embodiments and the following detailed description thereof are merely exemplary aspects of the teachings of this disclosure and are not restrictive.DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1A is a perspective view of a semiautomatic firearm in accord with the inventions herein.

[0017] FIG. IB is a more detailed perspective view of the semiautomatic firearm of FIG. 1.

[0018] FIG. 2 is a perspective view of a molded stock for receiving the receiver, barrel, and trigger and firing mechanism of a firearm.

[0019] FIG. 3 is a side-lateral cross-sectional view of a portion of a firearm.

[0020] FIG. 4 is a top-lateral cross-sectional view of a portion of a firearm.

[0021] FIGS. 5 A through 5C are conceptual diagrams further illustrating the bolt assembly, firing pin assembly, and trigger assembly of a firearm.

[0022] FIGS. 6 A through 6D are conceptual diagrams illustrating various view of trigger components of a firearm.

[0023] FIGS. 7A through 7K are conceptual diagrams illustrating an example firing and reset sequence of trigger assembly of a firearm.

[0024] FIGS. 8 A through 8C are conceptual diagrams illustrating the trigger assembly with a hammer stop return spring, biasing element, and trigger bushing.

[0025] FIG. 9 is a photograph illustrating an example ruptured case.

[0026] FIG. 10 is a photograph illustrating an example ruptured case.

[0027] FIGS. 11 through 14 are conceptual diagram illustrating an example firing pin and bolt face of a firearm, which are configured to reduce or prevent case rupture.

[0028] FIGS. 15A through 15C are conceptual diagrams illustrating an example extractor of a push feed firearm.DETAILED DESCRIPTION

[0029] The design objective for the semi-automatic rimfire cartridge trigger assembly may include enabling an adjustable pull weight trigger with an internal safety catch. The design challenge that is presented in the semi-automatic configuration is that in traditional semi-automatic hammer fired trigger assemblies, such as an AR 15, the reset function of the assembly is directly linked to the trigger return spring. In adjustable non- semi-automatic triggers, the adjustability is achieved by changing the force in the trigger spring. This changing of the force in the trigger spring may be achieved by rotating the spring in a threaded hole. As the spring is rotated, the functional length of the spring is changed; thus, the force of the spring can increase or decrease, thus changing the force of the trigger pull.

[0030] Some fire control mechanisms may include a disconnector or reset that is directly linked to the trigger return spring and trigger. In such examples, if the trigger return spring force is adjusted to alter the trigger pull weight, it may adjust the point of reset of the trigger. In principle, there are two limits to a trigger reset function. The first limit is insufficient force to properly reset the trigger such that the hammer does not disengage from the disconnector. The second is where the trigger resets before the trigger is in proper position to sear up with the hammer, which may result in hammer released either after or before the bolt has gone into battery. A dead-trigger may result when the hammer strikes the bolt and firing pin prior to the bolt has gone into battery. Alternatively, successive fired round may result if the hammer strikes the bolt and firing pin after to the bolt has gone into battery.

[0031] If the trigger reset varies between these two limits, the trigger functions normally and the observed reset distance for the shooter may be controlled. For example, some shooters desire the reset distance to be short for rapid follow up shots requiring less back and forth movement of the trigger finger. Alternatively, some shooters may prefer the reset distance to be further forward, thus requiring more deliberate and longer releases of the trigger to achieve proper reset. Proper adjustment of the trigger reset may improve safety by preventing an unintentional trigger pulls.

[0032] FIGS. 1A, IB, and 2, are perspective views of an example semiautomatic firearm 30. Firearm 30 includes a housing 32 including a receiver 34 defining an opening 58 and ejector port 44, a barrel 36 with a bore 37 and a firing chamber 38, a stock 40 with a forestock portion 42, a trigger and firing assembly 46 with a safety mechanism 53, a bolt assembly 48 having a manual handle assembly 90 with a manual handle 92, and a magazine 52. In one example, trigger and firing assembly 46 may be inserted into stock 40 and forestock 42, which may include a unitary component as shown in FIG. 2. Barrel 36 and receiver 34 may be assembled on top of and coupled to trigger and firing assembly 46. Bolt assembly 48 and recoil spring assembly 50 may be inserted into a rear upward opening of receiver 34. Additional example components and example operations of firearm 30 are described in U.S. Patent Nos. 11,713,933; 10,788,277; 9,810,496; 9,599,417; and 9,513,076; the entirety of each of which are incorporated by reference herein.

[0033] FIG. 3 is a side-lateral cross-sectional view of a portion of firearm 30. As illustrated in FIG. 3, bolt assembly 48 is slidingly engaged in the receiver 34 to move forwardly and backwardly along a bolt assembly travel axis “aa” which also is also coincident with a barrel axis “ab” of the bore 37 and is generally a central axis of firearm 30 (FIG. 1A). Receiver 34 has an interior defining a breech region that receives bolt assembly48. Ledges on receiver 34 constrain bolt assembly 48 and provide bearing surfaces for sliding engagement with bolt assembly 48.

[0034] Bolt assembly 48 includes a bolt body 82 that may be a unitary form, a firing pin assembly 86, a retractable extractor 88, a manual handle assembly 90 with a manual handle 92, a bolt locking mechanism 93 including a movable member that moves upwardly and downwardly transverse to the axis aa. Bolt body 82 has a firing pin opening configured to received therethrough firing pin assembly 86. A bolt face 112 is defined on the forward face 68 of bolt body 82 and is defined by lip 114 which extends over an undercut region 115 and is generally of a circular shape, defining a cartridge head receiving region 118 (FIG. 11). Cartridge head receiving region 118 defines a flat surface that engages a cartridge 119. In operation, cartridge 119, such as a necked rimfire cartridge, is received in and seats against the planar bolt head space surface of undercut region 115.

[0035] FIG. 4 is a top-lateral cross-sectional view of a portion of firearm 30. As illustrated in FIG. 4, cartridge 119 is pushed into undercut region 118 by the retractable extractor 88. The cartridge 119 is a high power necked rimfire cartridge and may include a casing 121 with a casing head 122 and a rim 123, as well as a collar 125 and necked down portion 126 reduce the diameter of the casing to be sized for the bullet 127. Example necked rimfire cartridges may include, for example, the .17 HMR and .17 WSM.

[0036] Firing pin assembly 86, extractor 88 and bolt face 112 having cartridge head receiving region 118 with undercut region 115 has been found to reliably extract and eject cartridges, as well as support cartridges with reduced occurrences of casing rupture, in synergistic association with the componentry described herein and as such contribute to and are an integral part of providing a reliable, mechanically simple, semiautomatic firearm with improved performance, particularly for high power necked rimfire cartridges. Although describe herein with respect to rimfire cartridges, in some examples, the feature of one or more of firing pin assembly 86, extractor 88, and bolt face 112 may be configured to reduce or prevent cartridge rupture in centerfire ammunition.

[0037] FIGS. 5 A through 5C are conceptual diagrams further illustrating the bolt assembly 48, firing pin assembly 86, and trigger assembly 46 of fire arm 30. As illustrated in FIG. 5C, firing pin assembly 86 includes an elongate shaft defining the firing pin 162 and has a forward cartridge engagement tip 164 that has a spherical tip (i.e., a cylinder terminating in a hemispherical end) for engaging the primer retaining feature of a cartridge (e.g., rims of rimfire cartridges) and a blunt rearward end 168 that is struck by the hammer 47 of trigger assembly 46. Firing pin 162 may include one or more reduced diameter, or thinned, portions172 that defines a forward stop portion 176 and first forward stop surface 178. In some examples, firing pin 162 may include a second rearward stop portion and respective second stop surface defined by the rearward reduced diameter of a second thinned portion. Firing pin 162 is retained in an opening 100 of bolt assembly 48 by way of a pin 188 secured in a pin aperture of bolt assembly 48 and extending through a slot 190 in the rearward end portion 192 of the firing pin. A spring 193 is positioned in the firing pin opening 100 between a spring stop 194 on the firing pin and the spring stop surfacel04 defined in bolt body 82. The spring 193 provides a rearward bias to the firing pin.

[0038] The recoil spring assembly 50 has a shaft 204, which may optionally include an inner shaft portion and an outer shaft portion. A spring stop may be positioned on a forward end of the shaft 204. A housing engagement portion with an attachment lug connects to the shaft 204 and is secured thereto by a shaft end piece. A recoil spring 224 is positioned under compression on shaft 204 between the housing or receiver engagement portion and the spring stop. The assembly is inserted into the recoil spring assembly opening which is sized to allow freedom of movement of spring 224 and shaft 204, particularly to compress and expand.

[0039] Bolt locking mechanism 93 may function as described in, for example, U.S. Patent No. 11,713,933, previously incorporated by reference. For example, when the rimfire cartridge 119 is fired by impact with firing pin 162, the bolt assembly 48 cannot move rearwardly until movable member 94 is retracted. Since the force provided to retract the movable locking member is acting essentially at 90 degrees from the needed direction of retraction, there is a substantial force multiplication requirement of what is needed at the bolt to accomplish the retraction at movable member 94. In some examples, the spring force of the coil spring 224 can be adjusted to provide appropriate retraction resistance of movable member 94 to delay the retraction and blowback.

[0040] Firearms with delayed blowback mechanisms are known and firearms with firing pin blocks are known. See for example U.S. Patent Nos. 4,344,246; 1,737,974; 1,410,270; 6,782791; 3,857,325; 2,975,680; and 5,666,754. These patents are incorporated by reference for all purposes. Aspects of the instant application will be suitable for incorporation in known mechanisms.

[0041] Trigger assembly 46 includes a trigger mechanism housing 1058 which receives a trigger components 1059. The trigger components 1059 are generally movable components and pivot about shafts that are supported by trigger mechanism housing 1058.

[0042] FIGS. 6 A through 6D are conceptual diagrams illustrating various view of trigger components 1059 of firearm 30. Trigger components 1059 generally includes a hammer 47, a trigger 1084, a hammer stop 1086 (also referred to as a safety trigger or safety trigger component), disconnector 1088, and a manual safety mechanism 53. Manual safety mechanism 53 includes a single piece crossbar safety. The hammer 47 includes a head portion 1092 and a cam portion 1094 having separated by a stem portion 1096. The cam portion 1094 defines an aperture 1098 that is mounted to and rotates about a bushing 1100 and shaft 1101 to define a hammer pivot 1102.

[0043] In some examples, the cam portion 1094 further includes an arcuate cam surface 1105 and a sear engagement portion 1106, the sear engagement portion 1106 having a radially extending bearing face. The hammer 47 is also coupled with a biasing element 1112 which, in some embodiments, is a rotational spring that is rotated about and coupled to the hammer pivot 1102 with the free ends engaged, for example, with the trigger mechanism housing 1058. The hammer 47 can also include a capture feature 1116 having an engagement surface.

[0044] Trigger 1084 includes a finger hook portion 1122 and a sear portion 1124 having a sear surface cooperating with and being configured to engage the bearing surface of sear engagement portion 1106 of the hammer 47. The trigger 1084 can be mounted to a trigger pivot 1126 configured as a shaft or pin and defining a rotational axis and extending from the trigger mechanism housing 1058 along the rotational axis. In some embodiments, the trigger 1084 further defines a slot 1132 that extends into the finger hook portion 1122 and lies on a plane that is substantially perpendicular to the rotational axis. The trigger 1084 can also include an extended portion 1134 that is engaged with a firing trigger return spring 1136 that biases finger hook portion 1122 of the trigger 1084 in the forward direction 1081. The return spring 1136 may be engaged with a ledge or flange portion of the trigger mechanism housing 1058. In some embodiments, the trigger 1084 includes a cam engagement surface that engages the arcuate cam surface of the hammer 47. Return spring 1136 include an adjustment portion 1137, enabling adjustment of a spring force of return spring 1136 using a set screw to urge adjustment portion 1137 upward , thereby compressing return spring 1136.

[0045] The hammer stop 1086 can include a finger hook portion 1142 and can be pivotally mounted to the trigger pivot 1126. In some examples, the finger hook portion 1142 of the hammer stop 1086 is a flat structure, formed from, for example, sheet or plate, that is disposed in the slot 1132 of the finger hook portion 1122 of the trigger 1084. As a flat structure, hammer stop 1086 does not requiring a stamping and may interfaces through a slot1147 in hammer 47. The finger hook portion 1122 of the hammer stop 1086 can also include an aperture 1144. The aperture 1144 can be utilized for insertion of a pin or lock, effectively preventing movement of the trigger hook portion particularly with respect to the hook portion of the firing trigger component, which prevents the trigger 1084 from being actuated.

[0046] In some examples, the hammer stop 1086 includes a catch portion 1146 that is laterally adjacent to the hammer 47. The catch portion 1146 can resemble an inverted “J” shape. The hammer stop 1086 can also include an extended portion 1148 that is engaged with a return spring 1152. The return spring 1152 also is coupled to an rearward cross bar 1089 of disconnector 1088, rearward cross bar 1089 extends through a plane defined by hammer stop 1086. In this way, disconnector 1088 is decoupled from trigger 1084.

[0047] Functionally, the return spring 1152 exerts a return force on the extended portion1148 of the hammer stop 1086 urging the finger hook portion 1142 of hammer stop 1086 to be rotated to a full forward position within the slot 1132 of the trigger 1084. In this unactuated or default orientation, the catch portion 1146 is positioned so that the catch portion 1146 is in a rotational path through which the capture feature 1116 of the hammer 47 travels during firing and obstructs the hammer 47. Accordingly, the catch portion 1146 intercepts the capture feature 1116 of the hammer 47 if the catch portion 1146 of hammer stop 1086 has not first been rotated out of the rotational path 1162. Hence, the hammer stop 1086 provides an additional safety mechanism that helps prevent discharge of the firearm 1030 in the event of an unintentional release of the hammer 47, for example, during an impact event where the weapon becomes jarred to the extent that the sear portion 1124 of the trigger 1084 slips off the sear engagement portion 1106 of the hammer 47.

[0048] During such an impact event, the hammer stop 1086 may undergo rotational displacement that is commensurate with the rotational displacement of the trigger 1084. However, in some examples, the rotational displacement required to rotate the catch portion 1146 out of the rotational path 1162 of the capture feature 1116 of the hammer 47 is substantially greater than the rotational displacement required for the sear portion 1124 of trigger 1084 to disengage the sear engagement portion 1106 of the hammer 47. Accordingly, the hammer stop 1086 will generally still perform the function of intercepting the hammer 47 even if the hammer stop 1086 undergoes the same or even somewhat more rotational displacement than the trigger 1084 in an impact event.

[0049] Disconnector 1088 is pivotally mounted within the housing 1038 and distal to the hammer 47. In some examples, disconnector 1088 may be mounted to a left side of trigger1084 and rotatable about trigger pivot 1126. Disconnector 1088 includes rearward cross bar 1089, a forward edge 1264, a forward cross bar 1266. Hence, disconnector 1088 may be stamped from a single unitary component having two bends, i.e., rearward cross bar 1089 and forward cross bar 1266. Forward cross bar 1266 is configured to contact a leading edge 1187 of hammer stop 1086.

[0050] In some examples, the disconnector 1088 is configured and positioned so that the forward edge 1264 is engageable with the reset feature 1284 of cavity 1282 formed in the head portion 1092 of the hammer 47 when the hammer 47 is hyperextended. Herein, the hammer 47 is considered “hyperextended” when the head portion 1092 of the hammer 47 is displaced beyond where the head portion 1092 is located when in the fully cocked configuration. Functionally, disconnector 1088 captures the hammer 47 and prevents the hammer 47 from automatically re-firing.

[0051] In these ways, a reset function of disconnector 1088 is linked to hammer stop 1086, and independent from trigger return spring 1036 and a travel of trigger 1084, thus not restricting the adjustability in trigger spring 1036. During operation, after firing a first round, when disconnector 1088 captured hammer 47 (i.e., forward edge 1264 engages reset feature 1284 of cavity 1282), as trigger 1084 and hammer stop 1086 are released forward to reset the trigger: first, trigger 1084 and hammer stop 1086 move forward until trigger 1084 reaches the forward stop, being a position ready to accept hammer 47 and, second, hammer stop 1086 continues to rotate forward until its leading edge 1187 contacts cross bar 1266 on disconnector 1088 to disengage (also referred to as “kick”) forward edge 1264 from reset feature 1284. In other designs, trigger boss 1085 may provide the kick to push disconnector 1088 off hammer 47. By changing the kick to be performed by the return of hammer stop 1086, trigger spring 1036 can be adjusted without the reset being altered. This allows the reset to be favorably and consistently located ahead of the trigger release.

[0052] FIGS. 7A through 7K are conceptual diagrams illustrating an example firing and reset sequence of trigger assembly 1059. FIG. 7A is a left side view of trigger assembly 1059 having the trigger 1084 seared up with hammer 47, and ready to fire. Note the capture feature 1116 inside the slot 1147 of the hammer 47. If the hammer 47 were to disengage (i.e., unsear) with the trigger 1084, hammer 47 would be caught by the hammer stop 1086, preventing unintentional discharge.

[0053] FIG. 7B illustrates the hammer stop 1086 pulled flush to trigger 1084. Note the catch portion 1146 of the hammer stop 1186 is rotated past a blocking position of the capturefeature 1116 of the hammer 47. If the hammer 47 were to disengage with the trigger 1084 it would be unobstructed from forward travel.

[0054] FIG. 7C illustrates when the trigger 1084 is pulled with the hammer stop 1086, resulting in the trigger 1084 unsearing with the hammer 47.

[0055] FIG. 7D illustrates the hammer 47 rotating forward, contacting the firing pin and the bolt (not shown), resulting in ignition. Note the disconnector 1088 is rotated maximally counterclockwise; its travel limited by the trigger boss 1185 on the trigger 1084 just left of the axis of rotation.

[0056] FIG. 7E illustrates the rearward movement of the bolt to drive the hammer 47 backward. The hammer 47 contacts the forward edge 1264 of the disconnector 1088.

[0057] FIG. 7F illustrates the return spring 1152 positioned between the hammer stop 1086 and the disconnector 1088 which allows the disconnector 1088 to rotated clockwise by the momentum of the hammer 47 sufficiently for the hammer 47 to get underneath disconnector 1088, i.e., the hyperextended position, and now the hammer 47 is locked underneath the forward edge 1264 of the disconnector 1088.

[0058] FIG. 7G illustrates the same sequence as FIG. 7F but from the right side. The user is still holding the trigger 1084 and hammer stop 1086 together in the rearward position.Note the gap G between the forward cross bar 1266 of the disconnector 1088 and the leading edge 1187 of the hammer stop 1086. The compressive force in the return spring 1152 maintains the retention of the hammer 47 by the disconnector 1088.

[0059] FIG. 7H illustrates the user releasing the trigger 1084 and hammer stop 1086 forward. The trigger 1084 has rotated sufficiently back towards the hammer 47 to sear up when the hammer 47 is released by the disconnector 1088. The graphic appears to show the hammer 47 and trigger 1084 in contact but there is a very small gap.

[0060] FIG. 71 illustrates the user further releasing the trigger 1084, which allows further return movement of the hammer stop 1086. It moves forward until the leading edge 1187 of the hammer stop 1086 contacts the forward cross bar 1266 of the disconnector 1088. This is the start of the resetting function. The return spring 1152 can now begin to push the disconnector 1088 backwards until it releases the hammer 47 and completes the reset function. The trigger 1084 returns to the seared up position and is ready to fire again.

[0061] FIG. 7J illustrates a condition of unsearing before the hammer stop 1086 is returned to the forward position.

[0062] FIG. 7K illustrated the condition of unsearing in which the hammer stop 1086 arrests movement of the hammer 47, i.e., the hammer 47 locked to the hammer stop 1086, preventing further travel of the hammer 47.

[0063] FIGS. 8 A through 8C are conceptual diagrams illustrating the trigger assembly 1059 with a hammer stop return spring 1061, biasing element 1112, and trigger bushing 1087. As mentioned previously, the trigger return spring 1036 rotates the trigger back to the home position when the user’s finger is released. Additionally, when the user releases their finger from the trigger 1084 after firing, they are releasing force on both the trigger 1084 and the hammer stop 1086. Without the hammer stop return spring 1061, the hammer stop 1086 may not be able to provide the “kick” to rotate the disconnector 1088 from contact with the hammer 47. Without the hammer stop return spring 1061, the hammer 47 may not release from the disconnector 1088 to the seared up with the trigger 1084. Since the hammer stop return spring 1061 is what provides the reset function (disconnecting the hammer 47 from the disconnector 1088), and is not affected by the adjust of trigger spring 1036, the trigger assembly 1059 can be adjusted for trigger pull without it affecting the function of the reset.

[0064] In some examples, hammer stop return spring 1061 may include a double torsion spring. The legs of the torsion spring are in contact with the floor of the trigger housing (not shown) and the crossbar is over the top of the trigger into the corner / upper edge of the hammer stop. This provides a rotational force on the hammer stop 1086 at all times. In some examples, hammer stop return spring 1061 is assemble to a boss 1091 on left side of the trigger 1084 and a trigger bushing 1087 on the right side of the trigger. Using only one boss may enable trigger 1084 to lay flat during manufacturing, such as during sintering or handling without the need for custom handling trays. In this way, trigger bushing 1061 allows the torsional hammer stop spring to assemble in a normal symmetric fashion without two opposing integrally molded trigger bosses.

[0065] The in-process addition of the .17 WSM cartridge to semi-automatic rimfire cartridge trigger assemblies has resulted in several design challenges. The main obstacle being that related to the ignition system and case support of the higher pressure WSM cartridge. Magnum rimfire cartridges in general (.17 HMR, .22 WMR, .17 HM2) are difficult to chamber in semi- automatics due to the ratio of higher pressure and thin walled brass. The timing must be very precise. The original A-Series locking system (available from Savage Arms, Westfield, Massachusetts) is highly effective at providing this precise timing. The system uses a round firing pin that transitions to a chisel type bladed front. Rimfires typically utilize a flat style firing pin that rides in a slot. The A-Series delayed blowback lockingsystem uses a round firing pin so that it may have the slot that interfaces with the locking lug, which also functions as a firing pin block.

[0066] Some bolt face and firing pin configurations may result in a particular types of case rupture / tearing where the overlapped section of the rim can deform into the firing pin hole. For example, FIG. 9 is a photograph illustrating an example ruptured 17 WSM case depicting a tear at the location of the firing pin indent. As another example, FIG. 10 is a photograph illustrating an example 17 WSM case rupture downward through the open area of the control round feed.

[0067] To reduce or substantially prevent deformation of ruptured higher pressure cartridge casing into the firing pin indent, the present disclosure describes an offset spherical tip firing pin with a smaller hole into the bolt face. FIGS. 11 through 14 are conceptual diagram illustrating an example firing pin 86 and bolt face 112 of firearm 30 that is configured to reduce or prevent case rupture.

[0068] Firing pin 86 includes an offset spherical tip firing pin with a smaller hole into the bolt face 112 compared to firearms without an offset spherical tip, such as a blade tip or the like. This configuration of firing pin 86 reduces a size of firing pin hole 119 in bolt face 112 to prevent the brass case from deforming into hole 119. Additionally, it allows for a more precise, energy-efficient indent of firing pin 86. In some examples, the size, shape, and location of the spherical tip of firing pin 86 are specific to the 17 WSM cartridge.

[0069] In some examples, higher pressure rimfire cartridges may be more susceptible to case rupture due to the controlled round feed geometry of the bolt faces. For example, case rupture with 17 WSM and / orl7 HMR cartridges, even in non- semi- automatic firearms, may result in the bottom of the case rim deforming downward through open area of the bolt face.

[0070] In order to help reduce or prevent this type of case rupture, bolt face 112 has a more of the diametral portion of the head space relative to other push feed or round feed systems. For example, the only portion that is not covered is the slot 100 that provides clearance for the fixed ejector. Note that for the 17 WSM it still retains the offset firing pin. In principle, this configuration is far less likely to experience a case rupture due to the geometrical constrains of a typical control round feed system.

[0071] A subsequent design challenge for this type of configuration is the extractor design. Push feed bolt assemblies generally use a laterally moving extractor, e.g., the extractor is flush with the face of the bolt and is biased by the spring underneath it towards the center of the bolt face. There is a chamfer on the extractor towards the center. This allows the recessed lip on a rimless cartridge (or the rim on a rimmed cartridge) to bias theextractor outward so it can properly seat onto the bolt face and then allow for the extractor to snap over it. Rimfire control round feed systems typically use the rotating hook design. This type of extractor is typically simpler and has the added benefit of the leading edge that can positively influence the ejection pattern. Stable, reliable ejection patterns can be difficult to achieve in a semi-automatic rimfire as the bolt velocities can be quite high for the very small casings.

[0072] As the push feed rimfire bolt face does not use the lateral moving style extractor typical of push feed systems, the feeding of the cartridge becomes a challenge. This may be exacerbated by semi-automatic aspect as the bolt is not pushed into battery by the user but by the recoil mechanism, which may have limited force at the very end of the stroke. More specifically, there is a certain amount of force required to position the cartridge underneath the extractor. This is less of an issue with a control round feed system, as the cartridge slips behind the extractor during feeding. With a push feed semi-automatic design, it would be beneficial to create an extractor design that does not require a lot of force to position the cartridge underneath the extractor, thereby constraining the recoil spring. In principle, a typical rimfire extractor is of the rotating claw shape would be incompatible with a push feed system, as the cartridge would interfere with the extractor. It is desirable to use a claw extractor design as it is arguably simpler than the typical push feed extractor. In parallel with the push feed bolt, a “hybrid” extractor that will allow for proper feeding.

[0073] FIGS. 15A through 15C are conceptual diagrams illustrating an example hybrid extractor 88 to provide proper feeding with a push feed bolt design. FIG. 15A depicts a 17 WSM cartridge 119 sliding up the push feed bolt face 112, about to contact with extractor 88. As the cartridge slides up the push feed bolt face, the specific geometry of extractor 88 allows the cartridge 119 to displace extractor 88 and allow the cartridge to properly seat in the bolt face. For example, FIG. 15B illustrates a top down cross section view of cartridge 119 in front of extractor 88. The tip 1502 of extractor 88 is against the outer radius of cartridge rim 123, thus enabling the cartridge rim 123 to bias extractor 88 and properly seat into the bolt face 112. In some examples, extractor 88 may include a surface polished to reduce friction between the tip 1502 of extractor 88 and cartridge rim 123 to improve force transfer from cartridge 119 to extractor 88 to bias extractor 88. Specifically, edged 1504 and 1506 may be polished or deburred to reduce snagging or friction between extractor 88 and cartridge rim 123. Additionally, note the beveled edge 113 of the headspace enabling cartridge rim 123 to be located in bolt face 112. FIG. 15C illustrates cartridge 119 fully seated in bolt face 112and engaged with extractor 88, with bolt 112 translucent and the extractor spring not shown. This style of bolt face may also be applicable on other non-semi-automatic WSM platforms.

[0074] Various components of firearm 30 as described herein may be conventionally manufactured from steel. In some examples, other metals may be used. The components of the trigger assembly cluster are generally conventionally formed from steel or other metals. In some instances, polymers may replace some components. For example the trigger mechanism housing may be made from polymers and composite materials. Metal inserts may be used for particular areas requiring high strength such as attachment locations. The polymer may be overmolded over the insert capturing the insert. The stock can be formed from polymers or wood or composite materials.

[0075] The following clauses illustrate example subject matter described herein.

[0076] Clause 1. A trigger assembly of a semi-automatic firearm, the trigger assembly comprising: a hammer rotatable about a first axis, the hammer including structure defining a capture feature and a reset feature; a trigger rotatable about a second axis, the trigger comprising: a first finger hook and a sear portion releasably coupled to the hammer; a trigger spring configured to urge the trigger toward a battery position, wherein the trigger spring is adjustable to alter a spring force applied to the trigger; a disconnector rotatable about the second axis, the disconnector comprising a forward edge configured to engage with the reset feature of the hammer; a hammer stop rotatable about the second axis, the hammer stop comprising a catch configured to, when the hammer stop is in a battery position, arrest the capture feature of the hammer as the hammer rotates to prevent discharge of the semiautomatic firearm; and a reset spring coupled between the hammer stop and the disconnector, wherein the reset spring is configured to urge the disconnector toward a position configured to engage with the reset feature defined by the hammer.

[0077] Clause 2. The trigger assembly of clause 1, wherein the hammer stop further comprises a reset spring portion configured to engage and support the reset spring.

[0078] Clause 3. The trigger assembly of clause 1 or 2, wherein the hammer stop comprise a safety trigger comprising a second finger hook having a portion extending forwardly of the first finger hook when the trigger assembly is in a battery position, and wherein, by rotation of the hammer stop, when the portion of the safety trigger is flush with the first finger hook portion, the catch of the hammer stop is positioned to allow free rotation of the hammer.

[0079] Clause 4. The trigger assembly of any one of clauses 1 through 3, wherein the forward edge of the disconnector is configured to engage with the reset feature of the hammer when the hammer is driven backward by a bolt after firing.

[0080] Clause 5. The trigger assembly of any one of clauses 1 through 4, wherein the hammer stop, when rotated from the battery position, is configured to kick the forward edge of the disconnector from engagement with the hammer.

[0081] Clause 6. The trigger assembly of any one of clauses 1 through 5, wherein the hammer defines an elongate slit or aperture configured to receive at least a portion of the catch of the hammer stop therethrough.

[0082] Clause 7. The trigger assembly of any one of clauses 1 through 6, wherein the hammer stop comprises a planar component.

[0083] Clause 8. The trigger assembly of any one of clauses 1 through 9, wherein the reset spring comprises a compression spring.

[0084] Clause 9. The trigger assembly of any one of clauses 1 through 8, wherein the disconnect further comprises a over-rotation stop and the trigger further comprises a boss protruding into a plane defined by the disconnector, and wherein, when the trigger is rotated about the first axis, the over-rotation stop configured to contact the boss to prevent an overrotation of the disconnector.

[0085] Clause 10. The trigger assembly of any one of clauses 1 through 9, wherein the trigger assembly further comprises a cross bar safety configured to, when in the safe-on position, prevent a rotation of the trigger about the first axis.

[0086] Clause 11. The trigger assembly of any one of clauses 1 through 10, wherein the trigger spring is configured to enable adjustment of the spring force applied to the trigger in a rotational range wherein the trigger is seared to the hammer.

[0087] Clause 12. The trigger assembly of any one of clauses 1 through 11, wherein the trigger assembly comprises passive and redundant safety mechanisms to prevent unintentional firing when the firearm is in a firing mode, wherein at least one safety mechanism includes a blocking member operatively coupled with the hammer stop for maintaining the blocking member in a blocking position when the hammer stop is in a battery position, the blocking member blocking the firing trigger component when in the blocking position to prevent release of the sear portion from the hammer, the blocking member being operatively coupled with the hammer stop for moving the blocking member out of the blocking position by moving the hammer stop out of the battery position to enable release of the sear portion from the hammer.

[0088] Clause 13. The firearm of any of the preceding clauses, wherein the blocking member includes an arcuate base portion rotatable about a third axis, the arcuate base portion defining a recess and being operatively coupled with the hammer stop for rotation about the third axis, wherein: the arcuate base portion blocks the firing trigger component from being actuated when the hammer stop is in the battery position; and the recess aligns with the firing trigger component when the hammer stop is rotated out of the battery position to enable the firing trigger component to release the hammer.

[0089] Clause 14. The firearm of any of the preceding clauses, wherein the blocking member includes a lever portion operatively coupled with the hammer stop for rotation about a third axis, wherein the lever portion blocks an underside of the firing trigger component to prevent disengagement of the firing trigger component from the hammer, the lever portion being maintained in the blocking position by the hammer stop when the hammer stop is in the battery position, the lever portion being selectively rotatable out of the blocking position by rotating the hammer stop out of the battery position.

[0090] Clause 15. The firearm of any of the preceding clauses, wherein the trigger assembly further comprises a manual safety mechanism actuated by a push button forward of the first finger hook portion and laterally actuated for selectively placing the firearm in one of a safety mode and a firing mode, the manual safety mechanism being operatively coupled to the blocking member for preventing the hammer stop from moving the blocking member out of the blocking position when in the safety mode, and enabling the hammer stop to move the blocking member out of the blocking position when in the firing mode.

[0091] Clause 16. The firearm of any of the preceding clauses, wherein the blocking member includes an arcuate base portion rotatable about a third axis, the arcuate base portion defining a recess and being operatively coupled with the hammer stop for rotation about the third axis, wherein: the arcuate base portion blocks the firing trigger component from being actuated when the hammer stop is in the battery position and when the firearm is in the safety mode and in the firing mode; and the recess aligns with the firing trigger component when the firearm is in the firing mode and the hammer stop is rotated out of the battery position to enable the firing trigger component to release the hammer.

[0092] Clause 17. The firearm of any of the preceding clauses, wherein the blocking member includes a lever portion that extends from the arcuate base portion and is operatively coupled with the hammer stop for rotation about a third axis, wherein the lever portion blocks the firing trigger component to prevent disengagement of the firing trigger component from the hammer, the lever portion being maintained in the blocking position by the hammer stopwhen the hammer stop is in the battery position and the firearm is in the firing mode, the lever portion being selectively rotatable out of the blocking position when the firearm is in the firing mode by rotating the hammer stop out of the battery position.

[0093] Clause 18. The firearm of any of the preceding clauses, wherein the blocking member includes a lever portion operatively coupled with the hammer stop for rotation about a third axis, wherein the lever portion blocks the firing trigger component to prevent disengagement of the firing trigger component from the hammer, the lever portion being maintained in the blocking position by the hammer stop when the hammer stop is in the battery position and the firearm is in the firing mode, the lever portion being selectively rotatable out of the blocking position when the firearm is in the firing mode by rotating the hammer stop out of the battery position.

[0094] Clause 19. A semiautomatic firearm comprising a trigger mechanism of any of the preceding clauses, wherein the semiautomatic firearm is chambered for one of .17 Winchester Super Magnum cartridge and .17 Homady Magnum Rimfire cartridge, the semiautomatic firearm comprising: a receiver with a barrel connected to a forward end of the receiver, and a reciprocating bolt assembly slidably engaged in the receiver, the bolt assembly comprising: a bolt body; and a firing pin extending longitudinally in the body, wherein the bolt assembly and receiver define a detent mechanism with a lug extending into the bolt body, the lug having opposing two greater surfaces, one facing forward and one facing rearward, the receiver having a more outwardly lug engagement surface positioned nearer the barrel, and a more inwardly lug engagement surface position more distal from the barrel, the more outwardly surface defining a locking position for the bolt assembly when the lug is engaged therewith, the plunger having an outward bias whereby retraction of the plunger is resisted thereby providing a delayed blowback of the bolt assembly upon firing a cartridge.

[0095] Clause 20. The semiautomatic firearm of clause 19, wherein the plunger has a blocking portion to block and not block the firing pin depending on whether the plunger is engaged with the more inwardly engagement surface or the more outwardly engagement surface.

[0096] Clause 21. The semiautomatic firearm of clause 19 or 20, wherein the lug is configured as a detent mechanism positioned in the bolt body and extending to engage the receiver for locking the bolt body in an in-battery position, the detent being provided with an outward bias with a spring force.

[0097] Clause 22. The firearm of clause 21, further comprising a recoil spring and wherein the recoil spring provides the spring force.

[0098] Clause 23. The firearm of any one of clauses 19 through 22, further comprising a firing pin extending through bolt body and wherein the detent comprises a movable member that moves between a first position and a second position, the movable member having a firing pin blocking portion such that when the movable member is in the first position the firing pin blocking portion is engageable with a stop portion on the firing pin to inhibit movement of the firing pin.

[0099] Clause 24. A semiautomatic firearm chambered for one of .17 Winchester Super Magnum cartridge and .17 Homady Magnum Rimfire cartridge, the semiautomatic firearm comprising: a receiver connecting to barrel with a firing chamber, a bolt assembly movable along a central axis within the receiver and slidingly engaged therewith, the bolt assembly comprising: a bolt body with a firing pin extending through the bolt body, the bolt assembly slidingly movable into and out of an in-battery position; a movable member extending outwardly from the bolt body and engaged with a surface external to the bolt assembly, whereby when the bolt assembly moves, the movable member is movable between an locked position and a non-locking position with a transition portion therebetween, the transition portion providing retention of the movable member in the locked position, and wherein when the blocking member is in the locked position the bolt assembly is in battery.

[0100] Clause 25. The semiautomatic firearm of clause 24, wherein the movable member is biased outwardly and the transition portion has an angled surface and the movable member is movable inwardly out of the locked position by rearward movement of the bolt assembly forcing the sliding engagement of the movable member with the angled surface thereby urging the movable member downwardly.

[0101] Clause 26. The semiautomatic firearm of clause 24 or 25, wherein the bolt assembly further comprises a firing pin that extends through the bolt body past the movable member, and when the movable member is not in the locked position, the movable member presents a blocking portion to block the movement of the firing pin.

[0102] Clause 27. The semiautomatic firearm of any one of clauses 24 through 26, wherein the movable member is lug shaped with a central T-shaped aperture and the movable member moves in an axis substantially normal to the central axis.

[0103] Clause The semiautomatic firearm of any one of clauses 24 through 27, wherein the movable member has a height, a width, and a forward-backward thickness, the heightbeing less than a height of the bolt body, the width less being than a width of the bolt body and the thickness less than the height of the movable member.

[0104] Clause 29. The semiautomatic firearm of any one of clauses 24 through 28, wherein the firing pin extends through a T-shaped aperture in the movable member.

[0105] Clause 30. The semiautomatic firearm any one of clauses 24 through 29, wherein the movable member has a distal end engagement surface that is chamfered and elongate in a direction normal to the central axis.

[0106] Clause 31. The semiautomatic firearm of any one of clauses 24 through 30, wherein the surface on the receiver is positioned such that when the bolt assembly is in an in battery position, the movable blocking member is in an outwardly position and indexed with a stop surface on receiver.

[0107] Clause 32. A firearm including a trigger assembly having passive and redundant safety mechanisms to prevent unintentional firing when the firearm is in a firing mode, the trigger assembly comprising: a hammer rotatable about a first axis, the hammer including structure defining a capture feature; a firing trigger component rotatable about a second axis and including a first finger hook portion, the firing trigger component including a sear portion releasably coupled to the hammer; and a hammer stop rotatable about the second axis and including a second finger hook portion, the second finger hook portion extending adjacent to and forwardly of the first finger hook portion when the trigger assembly is in a battery position, wherein a first of the redundant safety mechanisms includes a catch portion defined on the hammer stop and, when the hammer stop is in a battery position, is positioned for arresting the capture feature of the hammer as the hammer rotates, to prevent discharge of the firearm, wherein a second of the redundant safety mechanisms includes a blocking member operatively coupled with the hammer stop for maintaining the blocking member in a blocking position when the hammer stop is in a battery position.

[0108] Clause 33. The firearm of clause 32, wherein the blocking member blocking the firing trigger component when in the blocking position to prevent release of the sear portion from the hammer, the blocking member being operatively coupled with the hammer stop for moving the blocking member out of the blocking position by moving the hammer stop out of the battery position to enable release of the sear portion from the hammer.

[0109] Clause 34. Any of the firearms or mechanisms or systems disclosed herein.

[0110] Clause 35. A semi-automatic firearm for firing rimfire ammunition, the firearm comprising: a barrel defining a chamber for receiving and firing a rimfire cartridge; a receiver operatively coupled to the barrel; a bolt assembly operatively coupled to the receiver andadapted for loading, firing, and ejecting the rimfire cartridge, the bolt assembly defining and being translatable rearwardly along a central axis to a rearward position for withdrawal of a spent cartridge casing from the chamber and ejection of the spent cartridge casing, the bolt assembly being translatable from the rearward position forwardly for loading the rimfire cartridge from a magazine into the chamber, wherein the bolt assembly comprises: a bolt body with a forward bolt face; a recess defined on the forward bolt face for receiving a head of the rimfire cartridge, the recess being proximally bound by a base surface on the bolt face, the base surface being substantially normal to the central axis; a ledge portion that partially surrounds the base surface of the bolt face, the ledge portion including an arcuate portion and a substantially straight portion tangential to the arcuate segment, the arcuate segment defining a radius about the central axis, the ledge portion including an inclined face that defines a normal vector including an axial component parallel to the central axis that is directed toward the base surface, the ledge portion being configured to accept a rim portion of the rimfire cartridge; a retractable extractor disposed proximate the recess; and a firing pin that selectively extends into the recess in a direction normal to the base surface, the firing pin parallel to and non-concentric with the central axis to effect rimfiring of the rimfire cartridge.

[0111] Clause 36. The semi-automatic firearm of clause 35, wherein the retractable extractor comprises a bias portion configured to displace the extractor to receive a push fed rimfire cartridge, the retractable extractor being extendable over the base surface, the retractable extractor being substantially centered at a location diametrically opposed to a junction point of the straight portion and the arcuate segment.

[0112] Clause 37. The semi-automatic firearm of clause 35 or 36, wherein the firing pin comprising a spherical tip firing pin,

[0113] Clause 38. The semi-automatic firearm of any one of clauses 35 through 37, wherein the recess defined by the forward bolt face is substantially spherical.

[0114] Clause 38. The semi-automatic firearm of any one of clauses 35 through 37, wherein a diameter of the recess of the forward bolt face is less than about 10 percent greater than a diameter of the spherical tip firing pin.

[0115] Clause 39. The semi-automatic firearm of any one of clauses 35 through 38, wherein the recess defined by the forward bolt face is sized to substantially prevent a brass case from deforming into the recess.

[0116] Clause 40. The semi-automatic firearm of any one of clauses 35 through 39, wherein the spherical tip firing pin is configured to provide a precise and energy efficient indent to a rimfire cartridge.

[0117] Clause 41. The semi-automatic firearm of any one of clauses 35 through 40, wherein the axial component is in a range of 40 degrees and 70 degrees inclusive relative to the normal vector.

[0118] Clause 42. The semi-automatic firearm of any one of clauses 35 through 41, wherein the retractable extractor is a claw-type extractor.

[0119] Clause 43. A semi-automatic firearm, comprising: a bolt assembly including: a bolt with a bolt face, the bolt assembly defining a central axis and being translatable along the central axis; a recess defined on the bolt face, the recess being proximally bounded by a base surface on the bolt face, the base surface being substantially normal to the central axis; a ledge portion including an arcuate segment that partially surrounds the base surface of the bolt face, the arcuate segment defining a radius about the central axis, the ledge portion including an inclined face that defines a normal vector including an axial component parallel to the central axis that is directed toward the base surface; a retractable extractor disposed proximate the recess, the retractable extractor being extendable over the base surface; and a firing pin that selectively extends into the recess in a direction normal to the base surface; and a firing chamber distal to the bolt assembly, the firing chamber being concentric about a barrel axis, wherein the central axis and the barrel axis are parallel and non-concentric for seating a rim of a rimfire cartridge against the inclined face of the ledge portion so that the rim is partially captured by the ledge portion when the bolt assembly is engaged with the firing chamber.

[0120] Clause 44. The semi-automatic firearm of clause 43, wherein the retractable extractor comprises a bias portion configured to displace the extractor to receive a push fed rimfire cartridge, the retractable extractor being extendable over the base surface, the retractable extractor being substantially centered at a location diametrically opposed to a junction point of the straight portion and the arcuate segment.

[0121] Clause 45. The semi-automatic firearm of clause 43 or 44, wherein the firing pin comprising a spherical tip firing pin,

[0122] Clause 46. The semi-automatic firearm of any one of clauses 43 through 45, wherein the recess defined by the forward bolt face is substantially spherical.

[0123] Clause 47. The semi-automatic firearm of any one of clauses 43 through 46, wherein a diameter of the recess of the forward bolt face is less than about 10 percent greater than a diameter of the spherical tip firing pin.

[0124] Clause 48. The semi-automatic firearm of any one of clauses 43 through 47, wherein the recess defined by the forward bolt face is sized to substantially prevent a brass case from deforming into the recess.

[0125] Clause 49. The semi-automatic firearm of any one of clauses 43 through 48, wherein the spherical tip firing pin is configured to provide a precise and energy efficient indent to a rimfire cartridge.

[0126] Clause 50. The semi-automatic firearm of any one of clauses 43 through 49, wherein: the firing chamber includes structure defining a circular access opening and a ridge, the ridge including an edge that is immediately adjacent the circular access opening, and the retractable extractor engages the ridge to rotate the retractable extractor away from the recess when the firearm is in a firing position.

[0127] Clause 51. The semi-automatic firearm of any one of clauses 43 through 50, wherein the bolt assembly defines an off-axis bore that is parallel to and non-concentric with the central axis, the firing pin being disposed in the off-axis bore.

[0128] Clause 52. The semi-automatic firearm of any one of clauses 43 through 51, wherein the recess defines a channel and a channel opening on a lateral face of the bolt.

[0129] Clause 53. The semi-automatic firearm of any one of clauses 43 through 52, wherein the channel extends along a lateral axis that intersects the central axis.

[0130] When used herein, the terminology “connect to” or “attach to” do not require direct component to component connection and intermediate components may be present.

[0131] All of the features disclosed in this specification (including the references incorporated by reference, including any accompanying claims, abstract and drawings), and / or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and / or steps are mutually exclusive.

[0132] Each feature disclosed in this specification (including references incorporated by reference, any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

[0133] The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any incorporated by reference references, any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps ofany method or process so disclosed The above references in all sections of this application are herein incorporated by references in their entirety for all purposes.

[0134] Although specific examples have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement calculated to achieve the same purpose could be substituted for the specific examples shown. This application is intended to cover adaptations or variations of the present subject matter. Therefore, it is intended that the invention be defined by the attached claims and their legal equivalents, as well as the following illustrative aspects. The above described aspects embodiments of the invention are merely descriptive of its principles and are not to be considered limiting.Further modifications of the invention herein disclosed will occur to those skilled in the respective arts and all such modifications are deemed to be within the scope of the invention.

Claims

CLAIMSWhat is claimed is:

1. A trigger assembly of a semi-automatic firearm for firing rimfire ammunition, comprising: a hammer rotatable about a first axis, the hammer including a capture feature and a reset feature; a trigger rotatable about a second axis, the trigger comprising a sear portion releasably coupled to the hammer; a trigger spring configured to urge the trigger toward a battery position, wherein the trigger spring is adjustable to alter a spring force applied to the trigger; a disconnector rotatable about the second axis, the disconnector comprising a forward edge configured to engage with the reset feature of the hammer; a hammer stop rotatable about the second axis, the hammer stop comprising a catch configured to, when the hammer stop is in a battery position, arrest the capture feature of the hammer when the hammer stop is in a battery position; and a reset spring coupled between the hammer stop and the disconnector, wherein the reset spring is configured to urge the disconnector toward a position to engage with the reset feature of the hammer.

2. The trigger assembly of claim 1, wherein the hammer stop further comprises a reset spring portion configured to engage and support the reset spring.

3. The trigger assembly of claim 1, wherein the hammer stop comprise a safety trigger comprising a second finger hook having a portion extending forwardly of the first finger hook when the trigger assembly is in a battery position, and wherein, by rotation of the hammer stop, when the portion of the safety trigger is flush with the first finger hook portion, the catch of the hammer stop is positioned to allow free rotation of the hammer.

4. The trigger assembly of claim 1, wherein the forward edge of the disconnector is configured to engage with the reset feature of the hammer when the hammer is driven backward by a bolt after firing.

5. The trigger assembly of claim 1, wherein the hammer stop, when rotated from the battery position, is configured to disengage the forward edge of the disconnector from the hammer.

6. The trigger assembly of claim 1, wherein the hammer defines an elongate aperture configured to receive at least a portion of the catch of the hammer stop therethrough.

7. The trigger assembly of claim 6, wherein the hammer stop comprises a planar component and the reset spring comprises a compression spring.

8. A semi-automatic firearm for firing rimfire ammunition, comprising: a barrel defining a chamber for receiving and firing a rimfire cartridge; a receiver operatively coupled to the barrel; a bolt assembly operatively coupled to the receiver and adapted for loading, firing, and ejecting the rimfire cartridge, the bolt assembly comprising: a bolt body with a forward bolt face; a recess defined on the forward bolt face for receiving a head of a rimfire cartridge, the recess being proximally bound by a base surface on the bolt face; a ledge portion that partially surrounds the base surface of the bolt face, the ledge portion including an inclined face configured to accept a rim portion of the rimfire cartridge; a retractable extractor disposed proximate the recess; and a firing pin that selectively extends into the recess in a direction normal to the base surface, the firing pin being parallel to and non-concentric with a central axis of the bolt body; and a trigger assembly comprising: a hammer rotatable about a first axis, the hammer including a capture feature and a reset feature; a trigger rotatable about a second axis, the trigger comprising a sear portion releasably coupled to the hammer; a trigger spring configured to urge the trigger toward a battery position; a disconnector rotatable about the second axis, the disconnector comprising a forward edge configured to engage with the reset feature of the hammer;a hammer stop rotatable about the second axis, the hammer stop comprising a catch configured to, when the hammer stop is in a battery position, arrest the capture feature of the hammer; and a reset spring coupled between the hammer stop and the disconnector, wherein the reset spring is configured to urge the disconnector toward a position to engage with the reset feature of the hammer.

9. The semi-automatic firearm of claim 8, wherein the retractable extractor comprises a bias portion configured to displace the extractor to receive a push fed rimfire cartridge.

10. The semi-automatic firearm of claim 8, wherein the firing pin comprises a spherical tip.

11. The semi-automatic firearm of claim 10, wherein the recess defined by the forward bolt face is substantially spherical.

12. The semi-automatic firearm of claim 11, wherein a diameter of the recess is less than about 10 percent greater than a diameter of the spherical tip of the firing pin.

13. The semi-automatic firearm of claim 8, wherein the ledge portion includes an arcuate segment that partially surrounds the base surface of the bolt face, the arcuate segment defining a radius about the central axis.

14. The semi-automatic firearm of claim 13, wherein the retractable extractor is substantially centered at a location diametrically opposed to a junction point of a straight portion and the arcuate segment of the ledge portion.

15. A trigger assembly for a semi-automatic firearm for firing rimfire ammunition, comprising: a hammer rotatable about a first axis, the hammer including a capture feature and a reset feature; a trigger rotatable about a second axis, the trigger comprising a sear portion releasably coupled to the hammer; a trigger spring configured to urge the trigger toward a battery position;a disconnector rotatable about the second axis, the disconnector comprising a forward edge configured to engage with the reset feature of the hammer; a hammer stop rotatable about the second axis, the hammer stop comprising a catch configured to, when the hammer stop is in a battery position, arrest the capture feature of the hammer; and a reset spring coupled between the hammer stop and the disconnector, wherein the reset spring is configured to urge the disconnector toward a position to engage with the reset feature of the hammer.

16. The trigger assembly of claim 15, wherein the hammer stop may further comprise a reset spring portion configured to engage and support the reset spring.

17. The trigger assembly of claim 15, wherein the hammer stop may comprise a safety trigger having a portion extending forwardly of a finger hook of the trigger when the trigger assembly is in a battery position, and wherein, by rotation of the hammer stop, when the portion of the safety trigger is flush with the finger hook portion, the catch of the hammer stop may be positioned to allow rotation of the hammer.

18. The trigger assembly of claim 15, wherein the forward edge of the disconnector may be configured to engage with the reset feature of the hammer when the hammer is driven backward after firing.

19. The trigger assembly of claim 15, wherein the hammer stop, when rotated from the battery position, may be configured to disengage the forward edge of the disconnector from the hammer.

20. The trigger assembly of claim 15, wherein the hammer may define an aperture configured to receive at least a portion of the catch of the hammer stop therethrough.

Images