Abstract: A firearm and a method for configuring the firearm is described that, in one aspect, includes a tubular magazine having a mechanical connection arranged at one end, a cap having a mechanical connection and configured to cooperate with the mechanical connection arranged on the one end of the tubular magazine, a retaining mechanism arranged in the tubular magazine having a circumferential surface, the retaining mechanism having retaining mechanism locking components arranged on the circumferential surface, and the cap further including an internal peripheral surface having cap locking components arranged along the internal peripheral surface, the retaining mechanism locking components and the cap locking components configured to interact to keep the cap from rotating thereby preventing the cap from accidentally disconnecting from the tubular magazine.

Abstract: A firearm and a method for configuring the firearm is described that, in one aspect, includes a tubular magazine having a mechanical connection arranged at one end, a cap having a mechanical connection and configured to cooperate with the mechanical connection arranged on the one end of the tubular magazine, a retaining mechanism arranged in the tubular magazine having a circumferential surface, the retaining mechanism having retaining mechanism locking components arranged on the circumferential surface, and the cap further including an internal peripheral surface having cap locking components arranged along the internal peripheral surface, the retaining mechanism locking components and the cap locking components configured to interact to keep the cap from rotating thereby preventing the cap from accidentally disconnecting from the tubular magazine.

Abstract: Auto loading gas operated firearm capable of handling a variety of ammunition loads having one or more gas relief valves for the initial volume of the gas cylinder of the firearm, the valves having a leaf spring covering the gas apertures to control the flow of gas from the initial volume of the gas cylinder, and a shaped geometric body interposed between the spring and each aperture that interacts with the spring and aperture to form a seal footprint which is a circular line or ring, the spring preferably operating in a plane substantially perpendicular to the recoil axis of the firearm.