Image Number 4 for United States Patent #7975595.
A firearm having a bolt carrier comprising an operating rod slot that is open at an end of the bolt carrier. The bolt carrier also includes a cam slot extending from the operating rod slot. The firearm includes a bolt having a protrusion extending from the bolt which enters and is movable within the cam slot. The firearm further includes an operating rod comprising a piston and a foot. The foot is disposed within the operating rod slot to prevent the separation of the bolt from the bolt carrier and to connect the operating rod to the bolt carrier.