I can tell you three stories about wartime explosives, two directly involving me and one indirectly.
The latter first. The weekend my dad died, a fellow villager was restoring his garden wall. He found a rusty object built into the stones and took it into his workshop and tried to clean it with a wire brush and angle grinder. He showed a neighbour his find, who immediately identified it as a mortar bomb. The police were called, they called the army, who quickly identified it as a stokes mortar bomb, made in July 1916, it was primed and fused and they decided that an immediate, controlled detonation was the only course of action. The bomb was unstable and highly dangerous. An area in the finders garden was sandbagged off and the bomb, with a bit of added plastic, was exploded. The garden now has a rather fine pond in the crater.
The first instance involving me was in 1972. I was helping a farmer during harvesting and autumn planting. The farm was a disused RAF OTU bomber airfield where there was a flying and gliding club where I was a member. I ploughed up what I first thought was a large stone, but soon recognised it as a smallish bomb. It turned out to be an incendiary bomb (phosphorous). The RAF bomb disposal were duly called out and identified the bomb as primed and fused. It was disposed of, with the aid of plastic explosive on the spot with spectacular results. We later learnt that a wellington bomber, taking part in one of 'Bomber' Harris' 1000 bomber raids, crashed on takeoff on that spot, which is why there was an fused and primed bomb.
The third event started when my wifes uncle died. His solicitors handled all the formalities, including the sale of the house. We had a 'phone call informing us that the house sold very quickly (within three days of going onto the market). We had to clear the house within a week. I hired a large van, drove to Oxford and sorted the contents into two piles, one to go to the tip and one to take home to be sorted at our leisure. When it came to garden sheds, workshop and greenhouse, we just chucked everything into the van, dumped it all in my workshop and I sorted it out over the next few months. The deceased worked at the Morris car plant in Cowley, Oxford, which was turned over, in part, to the repair of damaged Hurricanes, where, I assume the hundreds of rounds of .303 machine gun ammunition came from, all of it live, some armour piercing, some tracer, some incendiary. I found it in the bottom of a large, wooden box. The ammunition was covered with all manner of nuts, bolts, old hinges etc, which is why I didn't notice it earlier. I spent an unpleasant afternoon with with the police, who were very interested in how I came into possession of the stuff.
<--Common Sense.