The disclosure relates to firearms, and more particularly to a caseless weapon for magazine, semi-automatic and automatic shot. The disclosed weapon includes: a removable adjustable front sight, a removable adjustable dioptrical sight, a forward grip, a gunstock, a magazine, a receiver cover, a cocking lever, a bolt carrier, a rod, a percussion piston, a shutter housing, a safety catch of the firing percussion, a balancing gear, a barrel, a barrel latch, a multifunctional cartridge, a conical bushing of receiver, an extractor, a receiver, a big front nut, a front swivel, a magazine latch, a magazine latch pusher, a safety latch, a safety catch, a trigger bar, a bracket of the percussion mechanism, a cocking piece, a multifunction latch lever, a stop of the multifunction latch, a lock pin splint, a latch of the ramrod, a spring of the latch of ramrod, a ramrod, a caseless ammunition.

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.

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.

A fire control group has a receiver having opposed sidewalls defining a space configured to receive a fire control group, the opposed sidewalls each defining a pivot pin aperture, the pivot pin apertures being registered with each other, a fire control group including a trigger received in the space, the fire control group defining a transverse pivot pin passage configured to be registered with the pivot pin apertures of the receiver, the fire control group including a pivoting operational element, the fire control group including a pivot pin supporting the pivoting operational element and received in the transverse pivot pin passage and the pivot pin apertures, the firearm having a hand grip aft of the trigger and defining a screw aperture, and a grip screw engaging the hand grip and engaging the fire control group. The grip screw may occupy a medial plane of the firearm.

A fire control group has a receiver having opposed sidewalls defining a space configured to receive a fire control group, the opposed sidewalls each defining a pivot pin aperture, the pivot pin apertures being registered with each other, a fire control group including a trigger received in the space, the fire control group defining a transverse pivot pin passage configured to be registered with the pivot pin apertures of the receiver, the fire control group including a pivoting operational element, the fire control group including a pivot pin supporting the pivoting operational element and received in the transverse pivot pin passage and the pivot pin apertures, the firearm having a hand grip aft of the trigger and defining a screw aperture, and a grip screw engaging the hand grip and engaging the fire control group. The grip screw may occupy a medial plane of the firearm.

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 plurality of retention facilities each operable to selectively restrain the hammer in the cocked position, and when the selector is in the first position to enable discharge of the firearm in response to movement of the trigger to the rearward 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.

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 plurality of retention facilities each operable to selectively restrain the hammer in the cocked position, and when the selector is in the first position to enable discharge of the firearm in response to movement of the trigger to the rearward 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.

A firearm operating system includes a housing, a central pivoting member disposed within the housing, a trigger including a portion disposed within the housing and a portion extending outside the housing such that the portion of the trigger within the housing includes a hole and at least one finger that extends in a first direction from the hole. Due to movement of the trigger, the at least one finger presses against the central pivoting member to cause the central pivoting member to rotate.

A firearm operating system includes a housing, a central pivoting member disposed within the housing, a trigger including a portion disposed within the housing and a portion extending outside the housing such that the portion of the trigger within the housing includes a hole and at least one finger that extends in a first direction from the hole. Due to movement of the trigger, the at least one finger presses against the central pivoting member to cause the central pivoting member to rotate.

Linear trigger mechanisms for firearms include a trigger slide mounted on, and configured to move linearly in relation to a chassis; and a hammer. The trigger slide has a rolling element, such as a pin-mounted roller or a rolling pin, that engages a contact surface on the hammer and thereby restrains the hammer against its spring bias. When the user pulls the trigger to discharge the firearm, the trigger slide moves linearly, causing the rolling element to roll off of the contact surface and thereby release the hammer. The trigger mechanisms can be equipped with a drop safety that rotates in response to an impact between the firearm and the ground, so as to interfere with the movement of the trigger slide and prevent the release of the hammer.