A firearm assembly, capable of firing bullets, includes a firearm assembly kit and a firing control unit (“FCU”). The FCU, in one embodiment, is disassembled from a handgun which is operable by one hand and capable of initiating firing a bullet when a trigger of the FCU is pulled. The firearm assembly kit is configured to house the FCU to form an operable firearm resembling a semiautomatic rifle operable by two hands. The kit includes a grip module and an extended firing slide (“EFS”). The grip module includes a handgrip, an FCU housing, a trigger guard, and a magazine port, wherein the trigger guard is situated between the handgrip and the magazine port which is located in front of the handgrip away from the user. The EFS facilitates firing of bullets from a magazine inserted in the magazine port via an extended firing pin.

A modular bolt action rifle is provided, having an upper receiver configured to receive a bolt action bolt housing and bolt and a first universal fitting at a front of the upper receiver configured to receive one of a plurality of commonly sourced rifle barrels, and a lower receiver integral to or coupled to the upper receiver. The lower receiver is configured to receive commonly sourced fire control group components and a commonly sourced bolt action trigger mechanism. The lower receiver includes a second universal fitting at a rear of the lower receiver configured to receive one of a plurality of commonly sourced butt stocks.

A modular bolt action rifle is provided, having an upper receiver configured to receive a bolt action bolt housing and bolt and a first universal fitting at a front of the upper receiver configured to receive one of a plurality of commonly sourced rifle barrels, and a lower receiver integral to or coupled to the upper receiver. The lower receiver is configured to receive commonly sourced fire control group components and a commonly sourced bolt action trigger mechanism. The lower receiver includes a second universal fitting at a rear of the lower receiver configured to receive one of a plurality of commonly sourced butt stocks.

A weapon safety system with a target and a weapon with an automated lock. Each target is associated with an emitter which transmits a clearance signal that encodes an identifier. The encoded identifier may release the automated lock when received by a receiver attached to the weapon. In order to restrict the positions and orientations from which the weapon can fire to those surrounding the desired targets, shooting is enabled and the automated lock is released, when the following conditions are met: the clearance signal is received by the receiver, so that the receiver is within a first enablement area generated by a first aperture in the emitter; a measured optical power is above a predefined threshold; and the encoded identifier is validated.

A weapon safety system with a target and a weapon with an automated lock. Each target is associated with an emitter which transmits a clearance signal that encodes an identifier. The encoded identifier may release the automated lock when received by a receiver attached to the weapon. In order to restrict the positions and orientations from which the weapon can fire to those surrounding the desired targets, shooting is enabled and the automated lock is released, when the following conditions are met: the clearance signal is received by the receiver, so that the receiver is within a first enablement area generated by a first aperture in the emitter; a measured optical power is above a predefined threshold; and the encoded identifier is validated.

A rifle or portable firearm assembly (e.g., 310) configured to work with user-actuable sensors and systems (e.g., S1-S4), comprises a removable receiver assembly 312 attached to and responsive to a trigger assembly 50 which are removably received in a stock or chassis 316 having a middle section 324 with a trigger motion sensing sidewall segment with at least one trigger motion sensor (e.g., 340L, 340R) which does not physically contact or attach to the trigger assembly and is instead spaced from every component of the trigger assembly when the receiver is installed in said stock or chassis. The trigger motion sensor is configured to sense, from a selected standoff distance, without contacting or interfering the trigger assembly in any way, at least one of (a) the trigger's first stage movement or (b) actuation of a safety lever, and generate a “trigger motion sensed” signal in response thereto.

A modular trigger control unit Is configured to be removably installed on a grip frame of a firearm and includes a locking block and a locking block pin. The trigger control unit has a protruding tab protruding rearward. The locking block includes slide rails extending forward, with each slide rail of the pair of slide rails having a flat wall extending downward with respect to the grip frame when the trigger control unit is installed on the grip frame. The trigger control unit is secured to the grip frame by: (1) the protruding tab received in a recess on an interior wall of a beavertail portion of the grip frame; and (2) the locking block pin traversing through a through hole on each flat wall such that removal of the trigger control unit from the grip frame requires removal of the locking block pin.

A modular trigger control unit Is configured to be removably installed on a grip frame of a firearm and includes a locking block and a locking block pin. The trigger control unit has a protruding tab protruding rearward. The locking block includes slide rails extending forward, with each slide rail of the pair of slide rails having a flat wall extending downward with respect to the grip frame when the trigger control unit is installed on the grip frame. The trigger control unit is secured to the grip frame by: (1) the protruding tab received in a recess on an interior wall of a beavertail portion of the grip frame; and (2) the locking block pin traversing through a through hole on each flat wall such that removal of the trigger control unit from the grip frame requires removal of the locking block pin.

A slidable trigger assembly for a firearm is described. The slidable trigger comprises a main body housing a trigger and a sear and a slider, slidably coupled with the main body. The slidable trigger assembly may include a slide adjuster configured to set the sear at a target position with respect to the slider. Alternatively, the slider moves laterally in response to physical manipulation of the slidable trigger assembly to set the sear at a target position with respect to the slider.

An apparatus implementable on a firearm includes a grip frame, a slide assembly, a trigger control unit, and a rail module. The trigger control unit is removably receivable in the grip frame and installed between the grip frame and the slide assembly such that, when operated, the trigger control unit causes firing of one or more rounds of ammunition. The rail module is configured to be installed between the trigger control unit and the grip frame to aid in securing the trigger control unit to the grip frame.