Apparatus and method for preventing the bolt carrier of a firearm from moving forward after firing the last round of ammunition, and signaling when the firearm has run out of ammunition.

Abstract

The invention is designed to be fitted into the AK47-type semiautomatic firearms to provide a missing but vital feature of locking the reciprocating bolt assembly of said firearm after having chambered, fired and ejected the last cartridge from its removable magazine. The invention is designed to be installed into the receiver portion of the firearm as well as incorporating a modification into the removable magazine housing and follower. The invention consists of a number of components that will work in cooperation with each other to provide the above desired feature.

1 . In a firearm, a mechanism for preventing a bolt carrier of the firearm from moving forward after having fired the last round of ammunition, and thereby providing a signal to indicate an empty condition of a magazine, the mechanism comprising: 
 a) a sensor lever pivotally connected to a receiver of said firearm;    b) a thumb release integral to the sensor lever;    c) a catch lever connected to the receiver of said firearm by use of a pivot pin;    d) a return spring removably attached to said catch lever;    e) a box magazine modified by a slot located at the top of the magazine opening; and    f) a tab permanently mounted on a magazine follower and protruding through said slot in the magazine housing.    
   
   
       2 . The mechanism of  claim 1 , wherein the firearm is an AK47-type or its variant.  
   
   
       3 . A method of preventing a bolt carrier of a firearm from moving forward after having fired the last round of ammunition, the method comprising the steps of: 
 a) sensing the absence of a cartridge in a magazine by the interaction of a tab on a magazine follower and a sensor lever pivotally mounted on a receiver of a firearm;    b) actuating by the sensor lever of a catch lever pivotally mounted on the receiver of said firearm; and    c) interrupting the forward motion of a the bolt carrier by a catch lever.    
   
   
       4 . The method of  claim 3 , wherein the firearm is an AK47-type or its variant.