Patent ID: 9038525
Filing Date: 2015-05-26
Classification: F16J,F41A

Abstract:
1. A firearm comprising: a bolt having a plurality of locking lugs; a piston formed on the bolt and having a plurality of rings configured to cooperate with the piston to mitigate gas leakage past the piston, each of the rings having a key formed thereon and a gap formed completely therethrough such that the gap of one ring is configured to receive at least a portion of the key of another ring; a bolt carrier to which the bolt is movably attached, the bolt carrier having a double cut cam; a weight movably disposed within the bolt carrier, the weight being configured to provide a forward and a rearward impact to offset rearward and forward bouncing of the bolt carrier; first and second springs contained within the bolt carrier that centrally bias the weight within the bolt carrier; a carrier key attached to the bolt; a tube configured to provide gas from a barrel of the firearm to the piston via the carrier key, the tube having a heat radiator formed on at least a portion of the tube; a gas metering plug having a gas metering hole configured to meter gas from the barrel of a firearm to the bolt carrier of the firearm, wherein the gas metering hole is located away from a gas port of the firearm; and a front sight block having a rear band and a front band for attaching the sight block to the barrel and having a gas passage formed in the front band for facilitating gas flow from the barrel to a gas tube of the firearm.