I though this was a cool box, so I brought it home to show to everyone.
That is a cool box.
What would these have been used for? My guess would be components certified to meet drawing specifications for assembly into ammunition used for test purposes such as calibration of chamber pressure measurement, muzzle velocity, etc. instrumentation.
There have been several threads on calibration components that a search should turn up. In fact, that exact same carton may be in one of the posts. I know that it is in HWS II.
In general Calibration Components are production control lots to verify production effectiveness. There are also Reference lots that are typically loaded rounds and Master Calibration lots which are a standard to which other calibration lots are compared. In short, they serve several purposes.