The Vuanguard bolt recall was to fix the shroud on the bolt that would alow the bolt to be inserted into the action at the wrong angle. If the shroud was at the wrong position the rifle would fire when the bolt was lowered. Sent three to be repaired myself. All they did was replace the bolt shroud with one that was shaped like the one on the Howa instead of the one that came on it that was shaped simular to the MK5.
