A trigger mechanism that can be used in AR-pattern firearms has a hammer, a trigger member, a disconnector, a locking member, and a “three position” safety selector having safe, standard semi-automatic, and forced reset semi-automatic positions. In the standard semi-automatic position, rearward movement of the bolt carrier causes rearward pivoting of the hammer such that the disconnector hook catches the hammer hook, at which time a user must manually release the trigger member to free the hammer from the disconnector to permit the hammer and trigger member to pivot to the set positions so that the user can pull the trigger member to fire the firearm. In the forced reset semi-automatic position, rearward movement of the bolt carrier causes rearward pivoting of the hammer causing the trigger member to be forced to the set position, the safety selector preventing the disconnector hook from catching the hammer hook, and thereafter when the bolt carrier reaches the substantially in-battery position the user can pull the trigger member to fire the firearm without manually releasing the trigger member. The locking member is pivotable between a first position at which the locking member mechanically blocks the trigger member from moving to the released position and a second position at which the locking member does not mechanically block the trigger member allowing the trigger member to be moved to the released position. The locking member is spring biased toward the first position and moved against the spring bias to the second position by contact from the bolt carrier during forward movement of the bolt carrier as the bolt carrier reaches a substantially in-battery position.

A trigger mechanism that can be used in AR-pattern firearms has a hammer, a trigger member, a disconnector, a locking member, and a “three position” safety selector having safe, standard semi-automatic, and forced reset semi-automatic positions. In the standard semi-automatic position, rearward movement of the bolt carrier causes rearward pivoting of the hammer such that the disconnector hook catches the hammer hook, at which time a user must manually release the trigger member to free the hammer from the disconnector to permit the hammer and trigger member to pivot to the set positions so that the user can pull the trigger member to fire the firearm. In the forced reset semi-automatic position, rearward movement of the bolt carrier causes rearward pivoting of the hammer causing the trigger member to be forced to the set position, the safety selector preventing the disconnector hook from catching the hammer hook, and thereafter when the bolt carrier reaches the substantially in-battery position the user can pull the trigger member to fire the firearm without manually releasing the trigger member. The locking member is pivotable between a first position at which the locking member mechanically blocks the trigger member from moving to the released position and a second position at which the locking member does not mechanically block the trigger member allowing the trigger member to be moved to the released position. The locking member is spring biased toward the first position and moved against the spring bias to the second position by contact from the bolt carrier during forward movement of the bolt carrier as the bolt carrier reaches a substantially in-battery position.

Trigger groups for striker-fired firearms have a frame defining a medial plane, a slide connected to the frame and operable to reciprocate between a forward battery position and a rearward recoil position, a barrel connected to the slide and having a forward muzzle end, a trigger assembly connected to the frame and movable between a forward trigger position and a rearward trigger position, a firing pin assembly connected to the slide and operable to reciprocate between a rearward retracted position and a forward extended position, the firing pin assembly including a forward-facing retention surface, the trigger assembly including a sear surface configured to selectively engage the retention surface to releasably restrain the firing pin assembly, a selector movable between a first selector position and a second selector position, and a connector operably engaged to the trigger assembly and to the selector.

Trigger groups for striker-fired firearms have a frame defining a medial plane, a slide connected to the frame and operable to reciprocate between a forward battery position and a rearward recoil position, a barrel connected to the slide and having a forward muzzle end, a trigger assembly connected to the frame and movable between a forward trigger position and a rearward trigger position, a firing pin assembly connected to the slide and operable to reciprocate between a rearward retracted position and a forward extended position, the firing pin assembly including a forward-facing retention surface, the trigger assembly including a sear surface configured to selectively engage the retention surface to releasably restrain the firing pin assembly, a selector movable between a first selector position and a second selector position, and a connector operably engaged to the trigger assembly and to the selector.

Trigger groups for semi-automatic firearms have a frame, a hammer connected to the frame and movable between a cocked position and a striking position, the hammer being biased toward the striking position, a trigger element connected to the frame and movable by a user between a forward position and a rearward position, a selector connected to the frame and movable between at least a first position and a second position, and a plurality of retention facilities each operable to selectively restrain the hammer in the cocked position, and when the selector is in the second position to enable discharge of the firearm in response to movement of the trigger to the forward position after movement to the rearward position and to enable an additional discharge of the firearm upon release of the trigger to the forward position.

Trigger groups for semi-automatic firearms have a frame, a hammer connected to the frame and movable between a cocked position and a striking position, the hammer being biased toward the striking position, a trigger element connected to the frame and movable by a user between a forward position and a rearward position, a selector connected to the frame and movable between at least a first position and a second position, and a plurality of retention facilities each operable to selectively restrain the hammer in the cocked position, and when the selector is in the second position to enable discharge of the firearm in response to movement of the trigger to the forward position after movement to the rearward position and to enable an additional discharge of the firearm upon release of the trigger to the forward position.

Trigger groups for semi-automatic firearms have a hammer, a trigger element, a sear, a selector, and a disconnector assembly, the disconnector assembly operable when the selector is in a first position to retain the hammer in the cocked position in response to release of the trigger element to the rest position subsequent to discharge of the firearm by pulling the trigger element, and the disconnector assembly operable when the selector is in a second position to release the hammer to the striking position in response to release of the trigger element to the rest position subsequent to discharge of the firearm by pulling the trigger element, such that the firearm discharges once per cycle of the trigger element when the selector is in the first position, and fires once for each forward or rearward motion of the trigger element when the selector is in the second position.

Trigger groups for semi-automatic firearms have a hammer, a trigger element, a sear, a selector, and a disconnector assembly, the disconnector assembly operable when the selector is in a first position to retain the hammer in the cocked position in response to release of the trigger element to the rest position subsequent to discharge of the firearm by pulling the trigger element, and the disconnector assembly operable when the selector is in a second position to release the hammer to the striking position in response to release of the trigger element to the rest position subsequent to discharge of the firearm by pulling the trigger element, such that the firearm discharges once per cycle of the trigger element when the selector is in the first position, and fires once for each forward or rearward motion of the trigger element when the selector is in the second position.

Trigger groups for semi-automatic firearms have a frame, a hammer connected to the frame and movable between a cocked position and a striking position, the hammer being biased toward the striking position, a trigger element connected to the frame and movable by a user between a forward position and a rearward position, a selector connected to the frame and movable between at least a first position and a second position, a disconnector having a hammer engagement facility adapted to selectably engage the hammer, a disconnector control element movable between a first control position and a second control position, the disconnector being operably engaged to the disconnector control element, the disconnector operable to move in a first range of motion when the disconnector control element is in the first control position, and in a second range of motion when the disconnector control element is in the second control position.

An operating system for a firearm includes a trigger, a hammer, a disconnector, a pivoting arm, and a lower member. The trigger includes a lower portion, an upper portion, and a trigger pivot. The disconnector includes a lower portion, an upper portion, and a disconnector pivot. The pivoting arm includes a forward protrusion, a pivoting arm opening, and a pin extending through the pivoting arm opening. The lower member includes a lower member opening and a pin hole that is coaxial with the trigger pivot and the disconnector pivot. At least a portion of the trigger and at least a portion of the disconnector are disposed within the lower member opening. Motion of the trigger causes the forward protrusion of the pivoting arm to engage a bolt carrier group and hold the bolt carrier group in an open position.