A collapsible firearm stock system is generally provided and preferably includes a shoulder stock system adapted to receive a buttstock thereon, and a locking linkage having a first linkage portion, a second linkage portion, and a hinge pin operatively uniting the first and said second linkage portions. One of the linkage portions is carried by the shoulder stock assembly so as to define a terminal end therefore, the other of the linkage portions being adapted to be carried by a firearm. Each of the linkage portions are adapted so as to automatically unite in locking engagement upon axial alignment of the shoulder stock assembly with the firearm about the hinge pin.