Pontius
Thanks for the response on bomb clearances. We TPs at BD generally flew as briefed or to flight test instructions. It would have been the boffins who issued the 0.3 second interval. Interesting.
Cannot imagine a pilot bringing back a stick of inerts on the doors. I once had a delayed release of a live 2,000 pnd target marker on to a Canberra's doors. There was no way of knowing then whether the arming wires had been pulled and it had barostatic fuzes to open a parachute and to light it up at lower altitudes. Pencil beam radar director of the Imber range talked me back to the release point where the target marker departed on opening doors. Pencil beam radar then followed the store measuring its trajectory. It was armed as I still had the arming wires and it did its thing on the way down. No significant damage to the doors.
Cannot recall whether the Vulcan had weapon bay door interlocks to prevent inadvertant drops on to closed doors. One would expect this to be a design requirement.