A firearm accessory attachment system and method are disclosed. The system has a first body having a first flanged protrusion coupled to the first body. The first flanged protrusion extends downward from the first body. A second flanged protrusion is coupled to and extends downward from the first body. The second flanged protrusion is positioned a first longitudinal distance from the first flanged protrusion. The system has a second body having a third flanged protrusion. The third flanged protrusion extends downward. The second body is movably coupled to the first body and slidable in a transverse direction. The system has an actuator configured to move the system between a locked configuration having a first envelope flange width defined by the first and third flanges and an unlocked configuration having a second envelope flange width. The second envelope flange width is less than the first envelope flange width.