Disclosed herein are reusable adapters for sighting devices for rocket launchers and other large weapons, particularly mounting adapters for reusable sighting devices that allow retrofitting of existing weapons inventory. Some embodiments include an adapter that includes a laser sighting device mount coupled to a mounting bracket, wherein the mounting bracket is configured to register to and align with one or more housing features of the rocket launcher. In various embodiments, the adapter also includes a strap member configured to secure and immobilize the adapter in position on the rocket launcher. In various embodiments, the laser sighting device mount may be factory calibrated with respect to the adapter, and therefore once the adapter has been mounted on the rocket launcher, no field calibrations of the laser sighting device are necessary.