Need to know something about metals.

[SilvercatMoonpaw]

Having read the tvtropes page on Fantasy Gun Control I thought about what would happen if your reversed that normal way the guns tend to get introduced to D&D-like faux-Medieval settings which is after the trope page proposes they should based on the setting's resemblance to Earth history.

If you flip around "all historical tech except guns => guns" you get "guns before history had them".  I'm a real amature at this, so this may be completely inaccurate, but my guess is that you only need two things to have guns:
1) gunpowder, which I'm guessing doesn't require a very advanced technology level to possibly create.
2) a material that can be made into cannons and gun barrels and doesn't then get destroyed when used.

It's #2 that I'm asking about: in terms of the evolving use of metals by Earth cultures (which I think goes: copper > bronze > iron/steel > better quality steel) what level of metal do you have to reach to make reasonable A) cannons, B) gun barrels?

Feel free to correct me on anything I got wrong.  The real point of the question is "What's the absolute earliest a culture could invent guns?" but I thought that might be too hard to answer in that form.

[Elemental_Elf]

Gunpowder is indeed fairly easy to make.

I believe most cannons were cast from Bronze until the late 19th century.

[sparkletwist]

http://home.att.net/~ShipmodelFAQ/ResearchNotes/smf-RN-Cannon-BvI.html

[SilvercatMoonpaw]

That certainly helps with the issue of cannons, but I'm still wondering if you could make the barrels of the various X-lock type guns out of bronze.

[Nomadic]

You can make a gunpowder fired gun from any material that can resist the pressure buildup. If it is a simple single shot pistol for example you could probably make it from sturdy wood. That sort of thing wouldn't have the huge pressure issues that you get with modern weapons. And yes you could use bronze just fine.

[SilvercatMoonpaw]

Ah, thank you, Nomadic.  You've been very, very helpful.

[Polycarp]

Indeed, there are cannons made from wood in the historical record, though none of them were particularly successful.  The rebels of the Ilinden Uprising (Macedonian revolt against the Ottoman Empire in 1903) used a cannon made out of a cherry tree log that, IIRC, is still a treasured state possession (despite the failure of both the cannon and the rebellion).

Of course, there are also cultural questions to consider here.  The Chinese used gunpowder as a weapon long before it was used in a "gun" per se - in fire lances, hand-held bombs, rockets, and so on.  It's been argued that the strategic considerations of China, which at the time fought principally with nomadic neighbors, was less conducive to the development of the cannon than Europe, where much smaller states with plenty of stone fortifications fought constantly.

What I'm trying to say is that "guns before history had them" makes much more sense when there's a justification for it, necessity being the mother of invention.  Archimedes invented a steam cannon, but it was rather garbage, and in any case the heavy encastellation of the middle ages was still a ways off.  Even if Archimedes himself had known about gunpowder then (and certainly the base ingredients were in existence at the time) it's still debatable whether the whole idea would have caught on.

[SilvercatMoonpaw]

That's really okay:  It was more of a curiosity: could the trope be somehow completely inverted rather than averted.

[SDragon]

The absolute earliest a culture can produce cannons is when they not only have a highly combustible material (IE, gunpowder) and a container to direct the pressure from the combustion of said material. I'm no expert, but I don't see too much difference-- on a conceptual level-- between the early Chinese rockets and a basic cannon.

Now that I think about it, Fantasy Firearms don't really need to rely on real-world gunpowder, either. The bark from the Burnalot tree, combined in equal parts with explodistone would work just as well. Sturdia wood could work for barrel material, too...