A quick mount for removably attaching an accessory to a longitudinal rail, the mount including a base having a first leg with a first undercut wall that engages a first longitudinal rail surface, a second leg opposite the first undercut wall, a retention plate rotatably mounted to the base adjacent the second leg and a bias element. The retention plate is operable in a secure mode in which the bias element urges the retention plate to rotate and engage a second undercut wall of the plate against a second longitudinal rail surface opposite the first surface and thereby clamp the mount to the rail. The retention plate is operable in a release mode where the second undercut wall disengages the second surface thereby releasing the mount from the rail. The mount can include a toggle lock to lock the plate in the secure mode. A related method is provided.