30x173mm Identification?

Hello everyone, I was looking for assistance with identification. It was given to me by my father who was in the Air Force when I was a child. He no longer remembers where or who he got it from but always assumed it was the 30x173mm for the GAU-8. I can’t find any markings on it and haven’t seen many with a polished casing, though this could have been done by a third party. I referenced this thread but could not make any connections: viewtopic.php?f=1&t=1255&hilit=GAU8

Let me know if better photographs are required and I’ll setup the DSLR and create a backdrop.

This looks like either a dummy or target practice GAU-8 projectile mated with a fired GAU-8 case that has been polished.

The bolt in the projectile leads me to believe that it was originally from a dummy round. Those cartridges usually had a bolt that ran from the primer pocket to the projectile, securing it in the case. The bolt on your projectile is short for that purpose though. It could be that the projectile was taken from a dummy and then someone replaced the bolt with a shorter one, but that’s just speculation on my part.

Thanks for the help two, I’ve seen others with the bolt you’re talking about running through the primer hole. If I wanted to remove 20 years of oxidation from the projectile, would 0000 steel wool and museum wax be the preferred course of action?

I haven’t done much restoration so I’m not sure of the best way to go about that unfortunately. I would actually be inclined to leave it as it is. Maybe some other members here who have more experience with restoration will chime in.