I did pic up some stuff off of a British Trawler that was sunk by a German u-boat in WW-2 . We found a grenade and several crates of 4" shells . Some of the crates were encrusted and the shells couldnt be removed . The shells we removed even had the brass arming tip that could be dialed in to a specific time and distance. I ended up giving this stuff over to the EOD at Marine base Cherry point . My wife thought is was gonna blow the house up. The EOD ended up coming to my house and actually beat the stuff with a hammer. I knew it wasnt still exsplosive because the casing was breached before I brought them to the surface. It made my wife happy