When I worked in West Africa for Schlumberger Wireline Services (oil well logging and perforating) in the early 1980's, we used perforating "guns" to open the steel oil well tubing up to allow oil to flow in and be pumped to the surface.
All of our equipment was mounted on either a big 6-WD Transtar truck for land wells or in a little cabin on an offshore oil rig. Either the truck or the cabin had a big winch mounted on it with about 20-25,000 ft of armored steel cable about 5/8" in diameter. The cable had seven conductors inside the armor and the steel sheath counted as an eighth conductor. The cable came off the reel and went around a big orange sheave (pulley) and then up to the top of the drilling derrick and then straight back down the hole. The gun would be hung on the end of that cable.
The gun was basically a section of very heavy-walled pipe with a set of radially arranged portals into which were screwed some shaped charges that looked about like a small softball with a segment cut-out. Inside the segment was a copper cone - and that formed a jet of molten copper when the charge was detonated down-hole. The copper jet would perforate the oil well tubing and fracture the geological formation and that would enable the oil or gas to flow (once some other stuff was done to the well).
Anti-tank artillery rounds work about the same way....I'm told.
I was trained on how to load the gun, set the primer cord and blasting cap and position it down-hole at the correct depth - and then set it off. I did this task many, many times - but I never actually
saw one of these things go off, because they were always 2-3 miles down-hole where the layer of petroleum in the local geological formation was located. We would confirm a good perforation by positioning a crewman on the drill floor and he would simply grasp the cable with his hand while I sent the electrical signal 10-15,000 ft. down to detonate the charges. If he felt a shudder in the cable, the charges
had definitely gone off.
No shudder = no detonation and then you had a dangerous situation where a live "gun" had to be brought up and dis-armed. Fortunately, this never happened to me so I never had to deal with it.
Anyhow, a story went around that a small village in South America was having some sort of religious celebration in the town square and some of the local-yokels who were employed as Schlumberger crewmen offered to supply the fireworks for the party. Apparently, they pilfered several shaped charges and some primer cord plus a few blasting caps and set the whole thing off in the crowded town square with a car battery -
ON THE SURFACE.
Much carnage and property destruction ensued as you can imagine.