Abstract: A handguard assembly and related method are provided. The handguard assembly can include a fastener assembly that installs in a handguard bore of a handguard. The fastener assembly can include a fastener head including first threads threaded in a first direction, a shaft extending from the fastener head, the shaft including second threads threaded in a second direction opposite the first direction, and a lock tab threadably engaging the second threads, the lock tab including a tab head. When the fastener assembly is converted from a retracted mode to an extended mode, the tab head can wedge into a barrel nut groove to secure the handguard to the barrel nut thereby impairing the handguard from rotating and/or sliding relative to the barrel nut. The shaft can thread into the lock tab when the fastener assembly is installed relative to the groove, with the overall length of the fastener assembly increasing as the tab head moves in the groove.

Abstract: An apparatus includes an adjustment knob, an inner locking ring, and an outer locking ring threadably coupled to the inner locking ring. The adjustment knob includes at least one tooth protruding radially inward from an inner peripheral edge of the adjustment knob. The inner locking ring includes at least one tooth protruding radially outward from the inner locking ring and configured to engage the at least one tooth of the adjustment knob to prevent rotational movement of the adjustment knob. The outer locking ring is configured to move the inner locking ring in a first axial direction toward the adjustment knob when the outer locking ring is rotated in a first rotatable direction. The outer locking ring is also configured to move the inner locking ring in an opposite second axial direction away from the adjustment knob when the outer locking ring is rotated in an opposite second rotatable direction.

Abstract: An apparatus includes an adjustment knob, an inner locking ring, and an outer locking ring threadably coupled to the inner locking ring. The adjustment knob includes at least one tooth protruding radially inward from an inner peripheral edge of the adjustment knob. The inner locking ring includes at least one tooth protruding radially outward from the inner locking ring and configured to engage the at least one tooth of the adjustment knob to prevent rotational movement of the adjustment knob. The outer locking ring is configured to move the inner locking ring in a first axial direction toward the adjustment knob when the outer locking ring is rotated in a first rotatable direction. The outer locking ring is also configured to move the inner locking ring in an opposite second axial direction away from the adjustment knob when the outer locking ring is rotated in an opposite second rotatable direction.