Patent ID: 8327749

Claim:
A firearm apparatus comprising: a firearm receiver housing a firing chamber, a firearm bolt, and a magazine well configured to accept a magazine of ammunition, where the firearm bolt can be in a locked-open state or a firing state; a magazine catch configured to retain a magazine inserted into the magazine well of the receiver; a bolt-catch device installed on the firearm receiver and configured to lock the bolt in a rearward open position; a magazine release button that is configured to manipulate the magazine catch when pushed in by a user to release the magazine from the magazine well; and a linking pin disposed between the magazine release button and the bolt-catch device, where the linking pin is configured to push the bolt-catch device to a position that locks open the firearm bolt in the locked-open state when the magazine release button is pushed in by a user, the linking in structured to move relative to the bolt-catch device and magazine release button.