	US 7,562,614 B2
	Closed bolt system with trigger assembly for converting a fully automatic submachine gun into a semi-automatic carbine
Timothy J. Polston, Jacksonville, Ark. (US)
Assigned to SA Ordinance, LLC, Tierra Verde, Fla. (US)
Filed on May 17, 2006, as Appl. No. 11/435,402.
Prior Publication US 2007/0266845 A1, Nov. 22, 2007
Int. Cl. F41A 5/00 (2006.01); F41A 3/00 (2006.01)

U.S. Cl. 89—139 [89/144; 89/145; 89/150; 89/154; 42/69.03]

22 Claims

1. A closed bolt system with trigger assembly for converting a fully automatic firing submachine gun into a semi-automatic firing carbine, the gun having a barrel and a trigger housing, the closed bolt system with trigger assembly comprising:

a) a bolt having a bolt lug disposed along a bottom side thereof and an axial bore formed therein, the axial bore receiving a firing pin tensioned by a spring, the firing pin having a tip portion at a front end extendable out of an open front end of the bolt and a rear wall at a back end for receiving contact by a tensioned hammer, the gun receiver enclosing the bolt;

b) a trigger member inserted within a cavity formed in the trigger housing, the trigger member having a finger engagement portion extending through the cavity into a trigger area of the trigger housing, the trigger member further having an upper portion for supporting an integral disconnector system;

c) the integral disconnector system including a disconnector arm and a disconnector, the disconnector arm having an upper top wall affecting the trigger assembly when the finger engagement portion of the trigger member is pulled backwards;

d) a tensioned sear having a finger member in contact with the disconnector arm upper top wall and a foot member for engaging the hammer;

e) the hammer having a nipple for engaging the sear foot member, the hammer tensioned by a spring and striking the firing pin when disengaged from the sear foot member;

f) a recoil spring positioned rearwardly of the bolt affecting backward and forward movement of the bolt;

g) a receiver for enclosing the bolt;

h) a pivot plate member having first and second inwardly extending posts;

i) a plurality of apertures formed in left and right sides of the gun trigger housing;

j) the trigger member upper portion having a second bore formed therein;

k) the hammer having a cylindrical portion and a central bore formed therethrough; and

l) the pivot plate first inwardly extending post inserted through at least one of the plurality of apertures formed in the gun trigger housing and securing the trigger member within the trigger housing cavity through the trigger member upper portion second bore and the pivot plate second inwardly extending post inserted through at least one of the plurality of apertures formed in the gun trigger housing and securing the hammer within the trigger housing cavity through the hammer central bore.