Patent ID: 9448027
Filing Date: 2016-09-20
CPC Classification: F41A

Claim Text:
1. A multi-caliber coupler assembly used to mount a hand guard assembly to the forward end of the upper receiver of a rifle and around a rifle barrel having a flange near its receiver end, said coupler assembly comprising: a generally cylindrical and open-ended barrel nut having a hollow interior, a barrel end, and a receiver end in an opposed position to said barrel end, said barrel nut further having interior fastening threads associated with said receiver end a portion of which extends centrally within said barrel nut, at least one threaded fastener hole associated with said barrel end, a plurality of aligned and spaced-apart exterior teeth extending radially outward from said barrel nut between said barrel end and said receiver end; an extension having a barrel end and an opposed receiver end, said extension also having two pieces configured for interlocking connection to one another yet remaining easily and promptly separable from one another, said receiver end of said extension having exterior fastening threads complementary to said interior fastening threads associated with said receiver end of said barrel nut such that a secure connection between said extension and said barrel nut can be achieved when said interior and said exterior threads are mated, said extension also having at least one rotation-assisting feature; at least one exterior-threaded fastener configured for receipt by and secured connection to said least one threaded fastener hole of said barrel nut, wherein when said interior fastening threads of said barrel nut engage the upper receiver of a rifle and provide secure connection of said barrel nut to the forward end of the upper receiver, and further when a rifle barrel is inserted through said hollow interior of said barrel nut so that its flange bottoms out against the forward end of the upper receiver, and in addition when said exterior fastening threads on said extension are mated within said hollow interior of barrel nut with said portion of said interior threads on said barrel nut extending centrally therein until said receiver end of said extension is positioned against the barrel's flange, trapping the flange between said extension and the upper receiver, and when said at least one exterior-threaded fastener is mated with said at least one fastener hole in said barrel end of said barrel nut until said at least one exterior-threaded fastener engages said extension, providing rotation-preventing connection between said extension and said barrel nut, many different hand guard assemblies can be mounted upon said aligned and spaced-apart exterior teeth extending radially outward from said barrel nut to the upper receiver of almost any automatic rifle, with said two-piece extension remaining readily removable from said barrel nut and providing prompt access to the rifle's barrel for quick barrel change.