I have come across a shell that has BLOCK BUSTER marked on the side (see top shell in below photo) and it seems these may have been made by a company called LOCK & LOAD. My web search has not revealed any company information by this name, only that they made a variety of LE type rounds; flechette, door breeching and the like. I don’t know what’s in this shell because the only other info is the hand written “RD BLK”. Havn’t figured the “RD” out yet.
If anyone has info on either BLOCK BUSTER or LOCK & LOAD I would be grateful because I’m having little luck.