Abstract: A pistol chassis is disclosed which may include a lower housing, an upper housing, a proximal enclosure, a distal sleeve, and a proximal accessory. The distal sleeve, lower housing, and upper housing may be secured together to form a tubular member for receiving a pistol. The lower housing further may include a distal segment, a proximal segment and an intermediate segment. The distal segment may include a pistol frame receptacle and a trigger guard enclosure. The proximal accessory may be a folding stock. The pistol chassis may house a pistol to produce a firearm apparatus.

Abstract: A bullpup shotgun which ejects shells from the bottom of its action has a reciprocable cover which, when in a closed position, overlies the breech end of the shotgun's barrel. When in an open position, the cover is in spaced relation to the barrel breech end, allowing access to the shotgun's action to clear an ammunition feed malfunction. The cover is mounted on a butt stock, and the butt stock may be movable relatively to the shotgun's receiver to effect motion of the cover between the open and closed positions.

Abstract: A pistol chassis is disclosed which may include a lower housing, an upper housing, a proximal enclosure, a distal sleeve, and a proximal accessory. The distal sleeve, lower housing, and upper housing may be secured together to form a tubular member for receiving a pistol. The lower housing further may include a distal segment, a proximal segment and an intermediate segment. Time distal segment may include a pistol frame receptacle and a trigger guard enclosure. The proximal accessory may be a folding stock. The pistol chassis may house a pistol to produce a firearm apparatus.