A backplate for a rifle may include a buffer tube engagement ring and an engagement tab operably coupled to the buffer tube engagement ring. The engagement tab may include a receiver engagement face and an exposed face that is opposite the receiver engagement face. The receiver engagement face may include a backplate protrusion extending away from a surface of the receiver engagement face, and a spring assisted guide spaced apart from the backplate protrusion. The spring assisted guide may include a cylindrically shaped cavity configured to receive and retain a distal end of a detent spring of the rifle.

Man portable weapons include integrated electronics that calculate orientation and movement in addition to providing that data to a user's heads-up displays (HUD) as well as to group and area networks. By passing data to a HUD, the user is able to see, virtually, the flight path, point of impact and other ballistic data as well as data representing the condition and performance of the weapon for any rounds fired. The HUD also displays the relative position of other members of the team, last known enemy area of operation and other useful parameters from the man portable weapons of the other team members through the network. The electronics may be integrated within the main components of any suitable man portable weapon in a non-intrusive way as to have no effect on the firing mechanism of the small arm when it is fully assembled.

Man portable weapons include integrated electronics that calculate orientation and movement in addition to providing that data to a user's heads-up displays (HUD) as well as to group and area networks. By passing data to a HUD, the user is able to see, virtually, the flight path, point of impact and other ballistic data as well as data representing the condition and performance of the weapon for any rounds fired. The HUD also displays the relative position of other members of the team, last known enemy area of operation and other useful parameters from the man portable weapons of the other team members through the network. The electronics may be integrated within the main components of any suitable man portable weapon in a non-intrusive way as to have no effect on the firing mechanism of the small arm when it is fully assembled.

In some embodiments, a firearm mechanism comprises a bolt carrier comprising a bolt carrier cavity, a buffer comprising a buffer cavity and a weight arranged to travel between the bolt carrier cavity and the buffer cavity. The buffer cavity comprises a damping mechanism comprising a reduction in a cross-sectional size of the buffer cavity. In some embodiments, the damping mechanism and weight comprise a valve arrangement arranged to pressurize the buffer cavity and damp kinetic energy carried by the weight.

A bolt carrier may be provided. The bolt carrier may comprise a counter-bore, a housing, a cap, and a free-floating mass. The counter-bore may be disposed in the bolt carrier. The housing may be disposed in the counter-bore. The housing may have an interior, a first end, and a second end. The cap may be disposed at the second end of the housing and may be connected to the bolt carrier. The free-floating mass may be slidably disposed in the housing. A length of the free-floating mass may be less than a length of the interior of the housing between the cap and the first end.

A semi-automatic or automatic rifle comprising a barrel attached to and upper receiver and including a compressible bolt carrier extension system. The compressible bolt carrier extension system includes a bolt carrier, an extension spring, two pins, and a reciprocation bolt carrier extension piece. As a whole, the compressible bolt carrier extension system makes possible the use of elongated upper and lower receivers to be used for chambering long-action or other center fire cartridges for use with AR rifles such as the M-16, and M4 etc., eliminating the need for any buffer or buffer tubes other than those commercially available. A further advantage of the compressible bolt carrier extension system is the reduction of felt recoil as the system fully loads during the recoil stroke as it pushes against the buffer absorbing additional recoil energy. The system can be incorporated into firearms using a variety of cartridges.

A semi-automatic or automatic rifle comprising a barrel attached to and upper receiver and including a compressible bolt carrier extension system. The compressible bolt carrier extension system includes a bolt carrier, an extension spring, two pins, and a reciprocation bolt carrier extension piece. As a whole, the compressible bolt carrier extension system makes possible the use of elongated upper and lower receivers to be used for chambering long-action or other center fire cartridges for use with AR rifles such as the M-16, and M4 etc., eliminating the need for any buffer or buffer tubes other than those commercially available. A further advantage of the compressible bolt carrier extension system is the reduction of felt recoil as the system fully loads during the recoil stroke as it pushes against the buffer absorbing additional recoil energy. The system can be incorporated into firearms using a variety of cartridges.

In some embodiments, a firearm mechanism comprises a bolt carrier comprising a bolt carrier cavity, a buffer comprising a buffer cavity and a weight arranged to travel between the bolt carrier cavity and the buffer cavity. The buffer cavity comprises a damping mechanism comprising a reduction in a cross-sectional size of the buffer cavity. In some embodiments, the damping mechanism and weight comprise a valve arrangement arranged to pressurize the buffer cavity and damp kinetic energy carried by the weight.

In some embodiments, a firearm mechanism comprises a bolt carrier comprising a bolt carrier cavity, a buffer comprising a buffer cavity and a weight arranged to travel between the bolt carrier cavity and the buffer cavity. The buffer cavity comprises a damping mechanism comprising a reduction in a cross-sectional size of the buffer cavity. In some embodiments, the damping mechanism and weight comprise a valve arrangement arranged to pressurize the buffer cavity and damp kinetic energy carried by the weight.

A backplate for a rifle may include a buffer tube engagement ring and an engagement tab operably coupled to the buffer tube engagement ring. The engagement tab may include a receiver engagement face and an exposed face that is opposite the receiver engagement face. The receiver engagement face may include a backplate protrusion extending away from a surface of the receiver engagement face, and a spring assisted guide spaced apart from the backplate protrusion. The spring assisted guide may include a cylindrically shaped cavity configured to receive and retain a distal end of a detent spring of the rifle.