This has been something misunderstood for years. The US Army put out a warning back in the 90s that you could not trust the color code on these and all items on training shelves were to be destroyed. The truth is that there is no color code or identification banding on the M42/46 or M77. We did a visit to the factory in the 1980s and were told that the ring was a result of the phosphate coating that was put on the bodies to prevent corrosion.
I contacted the source of the alert back in the 90s, he expressed concern that there were also reports of some observed in the field which were of other colors. Green, yellow, red, etc. I asked him if they had been found in New Mexico or Alaska. With some surprise he answered Alaska. I explained to him that most testing took place in WSMR in New Mexico, but in Ft. Greely Alaska they also did testing. The submunitions on inert or phase 1 subs (live det only) were painted different colors for each warhead. This allowed for pattern testing to be able to judge where each rocket on a sixpack was ending up. Since the submunition bodies were inert loaded, if the det was popped they were released as scrap.
Unfortunately, US submunitions are generally considered internal components. Paint is mainly there to prevent corrsion, not for marking purposes. Most subs are unmarked, unless specifically loaded for display or training. The closest thing that comes to mind as a possible exception is the BLU 97, which is painted yellow. If you pull apart a practice marked 155mm M483 from the 80s-90s you will find that the submunitions were unmarked, same as the live ones. Dispensers like the SUU-13 were the same. Inert markings on the dispensers and cannisters, submunitions unmarked.
