worst External damage ever.

[Sailor Steve]

I have one minor problem. If it was a destroyer and not a cruiser as originally identified, then it wasn't an 8" shell as those only come with heavy cruisers. It couldn't have been bigger than 5" if it was a destroyer. On the other hand destroyers didn't usually carry AP shells. They did carry a capped semi-AP called 'Common', but it was designed to go through small concrete bunkers.

Actually at the glancing angle seen in the photo and HE shell might have exploded outward, causing no damage to the pressure hull at all. Or it might have exploded on contact with the outer hull, peppering the pressure hull with shrapnel and maybe making a bunch of small holes or not penetrating. HE is designed to explode on contact, which is bad for single hulls but much better for double hulls, especially when the inner hull is thicker and stronger.

[edit] A little more digging:

Hyperwar quotes it as an 8" dud fired from one of the cruisers, which would have a fire-control system capable of hitting a submarine fairly easily at 9000 yards.
http://www.ibiblio.org/hyperwar/USN/....html#SS-320.1