Would it be possible to fire an explosive cannonball, similar to an artillery shell, using stone age technology?

Question

Ignoring how the stone age people acquired gunpowder (see this question), and manufactured cannons, (see this question) would it be possible for them to produce and fire effective shells made of stone and filled with gunpowder, which would explode after around ten seconds (time to light shell, load cannonball, and fire cannon), and actually result in significantly more damage than a normal cannonball?

I am mainly concerned about manufacturing an effective fuse, and making the walls thin enough to release a lot of energy from the explosion/create shrapnel, but not simply shatter when fired from the cannon.

Answer 1

As a conventional shell, I'd agree with No

Bear in mind that it took hundreds of years of experience with iron cannon before explosive shells replaced cannonballs around 1850. So historically, this didn't happen even when people had significant ironworking experience, never mind stone age methods. Even then there were many serious accidents.

If you want explosive projectiles, then you want bombs - earthenware sealed pots, full of gunpowder, with a fuse, and some form of catapult or trebuchet. Light fuse, lob bomb and hope. Note that the thicker you make the pot or jar, the bigger the explosion, because the contained pressures are higher. Firing it from a cannon is unlikely to work, simply because you will likely destroy the container or set it off - firing shells from cannons requires special, slower-burning powders to avoid destroying the shell.

Answer 2

The cannon is very problematic. If you are committed to cannons I think the all stone cannon is a nonstarter. Plus it seems a little bit Flintstones. Not that there is anything wrong with that.

But there is no reason stone age people could not make gunpowder. If your definition of "fire" means "propel towards the enemy at a fast rate" that could be done with Byzantine-style siege engines. The Byzantines definitely hurled ceramic "cannonballs" full of Greek fire at their enemies. They did not have gunpowder but would have thrown that too if they had.

ceramic Greek fire bombs from https://pceldran.wordpress.com/2015/02/11/byzantine-naval-warfare-siege-weapons-battle-tactics/

Your primitives could have a catapult or a trebuchet. Those require engineering sensibilities that I do not think existed until at least the Bronze age but they do not require metal. If a stone age engineer saw one working I bet he or she could copy it.

A stone bomb could be made but would be laborious. Late stone age tech included ceramics. You could fire a ceramic bomb from your catapult or trebuchet and that would work just fine. I do not remember Fred and Barney hurling explosives at anyone but they probably would if provoked.

Answer 3

No

As I understand it, your goal is to make an explosive shell that survives firing and explodes after impact (or just before impact, in the very best case). That is not easy with metal shells and cannon, doing it with stone shells will be ever so much harder.

• You need predictable fuses. Firing a muzzle-loader is a lengthy affair. If your fuse train is, say, 2 to 20 seconds, you have a high probability that it will blow in the barrel. High enough that you won't get any experienced artillerymen because they die first.
• Non-solid shells will be quite likely to shatter.
• Even if the shell survives, the fuse will affect ballistics. It might be blown free from the shell, it might be bashed in, etc.

But building an explosive shell that will survive a catapult launch is probably feasible.

Answer 4

No, Yes & Once

On Cannon:

No, the main problem is that we, lay people in 2017, have a good idea how cannon work. And stone age people just don't. Not anything near.

Yes, a time traveller with some time to get prepared for just this occasion. You know, know-how, how to get the stuff he needs for this project. No cheating by going to the hardware store.

Once, so you have everything build you think you need, aka stone bombard. You aim, not sure at what, as there are no villages to speak of to our modern eyes. Maybe a hill fort? You light the fuse and a few seconds later you find yourself facing your maker, trying to explain what you were doing. You just fired the first stone bomb in history.

Stone just has the wrong properties to create a cannon. Let alone an exploding cannon ball. Even the myth-busters used wood with iron rings, firing multiple times.

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On Cannonballs:

With a short google search of how to hollow out rocks does not show anything near what I think of as a Cannonball. There only seem to be hacked out basins. Hollow Rock is a training exercise, so it will not help you much.

Mind that the thin walls of cannonballs are quite hard to make in stone. I am thinking 2 bowls together. But that will give problems with where they meet.

I think Andrew Dodds answer gets as close as you can to things exploding.

Answer 5

Making a fuse is rather simple, use gunpowder and some dry leaf-like material to make it. Now for the cannonballs: Even with today's manufacturing methods making a hollow sphere is quite difficult, depending on the methods used. There are three ways I can think of to do so:

• Rapid-Prototyping / 3D Printing (whether it is plastics or metal)
• Casting (this is how the traditional cannonballs and cannons were made I guess)
• Manufacturing two bowls and fusing them together

If a way is found to glue stones together the first and the third way would work. As glue one could use clay.

How does Rapid-Prototyping / 3D-Printing work?

Material is added to a carrier-plate, and from there the wished structure is built up layer by layer, the thickness of the layer depends on the used machine and material. It is similar to how one makes pots out of clay.

Answer 6

Use coconuts, fired out of a wooden cannon.

A common design for early cannons IRL involved a barrel-like configuration of wooden planks held together with metal hoops - this is, in fact, the origin of why we call it the “barrel” of the gun. Needless to say, these early cannons had a tendency to violently explode, but it should be possible for a Stone Age society to build one, using rope or dried leather to hold it together.

Then, having constructed their cannons, they take a coconut (perhaps an inedible variety of them), drill a hole in it, then fill it full of gunpowder and stuff a fuse in the hole that was drilled. This solves the problems some other users mentioned with shattering your cannonball in the barrel of your gun, since your cannon is weak enough that any force sufficient to shatter your cannonball would also be sufficient to explosively shatter your cannons. Additionally, by weakening your cannons to prevent explosions, you reduce the air speed of your cannonballs, proportionally increasing the effectiveness of an explosive cannonball.