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So, due to reasons magical, civilization has aversion towards metals which are above antimony in reactivity series. Yet, that doesn't stop them from developing gunpowder and wooden cannons. But while wooden cannons made of hardened wood with a copper tube inside is cool, one wishes for more than just that, even if these special cannons would be rare.

So my question is, among the metals and alloys consisting solely of these metals, is there any that would compare to bronze in terms of both simplicity of making guns of(that is, it doesn't have too high a melting point), and does have qualities of cannon metal comparable to the gun bronze? Rarity of the material is not an issue, only the simplicity of working with and quality of the final product.

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  • $\begingroup$ Should I use hard science tag here? $\endgroup$ Dec 20, 2019 at 23:19
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    $\begingroup$ The chemical properties of an alloy are not similar to the properties of the components. Bronze is very different from copper, and very different from tin. Why would the magical properties of an alloy be similar to those of the components? $\endgroup$
    – AlexP
    Dec 20, 2019 at 23:23
  • $\begingroup$ Tbh, I am still adressing how I solve the effect of alloys, so I am looking of whether it is possible for me to do without the tin. $\endgroup$ Dec 20, 2019 at 23:27
  • $\begingroup$ tungsten can be used to make even advanced firearms, they will be heavy however, and you need a way to work it. If you just want something unreactive after it is made, gold-iron alloy is thing. keep in mind reactive is not a great predictor of how they will behave in the real world, both copper and silver is low on the table but corrodes very quickly. $\endgroup$
    – John
    Dec 21, 2019 at 17:31
  • $\begingroup$ Are we banning elements based on where they sit in a reactivity series as elements, or where the resulting alloy sits? It matters a lot for nickel (and other transition metals). $\endgroup$
    – user86462
    Feb 7, 2023 at 9:30

4 Answers 4

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Monel or its naturally occurring counterpart Cupronickel is probably your best bet. They are nickel-copper alloys that melts at 1300–1385C (hotter than bronze, but doable by your standard medieval blacksmith) and it's highly resistant to corrosion from acids, salt water, and high oxygen environments; so, it should be at least on par with antimony for corrosion resistance and fairly easy to to cast like bronze.

Monel 500-k vs Bronze 510 shows us that Monel has about 50% more yield strength than bronze; however, this is a comparison of high-end modern alloys that include trace amounts of aluminum, titanium, phosphorus, etc. which you would not expect to find in a fantasy setting.

If you are looking at possibilities for earlier firearms, you may be more interested in the relationship between Tin Bronze and Cupronickel as seen on this chart. At these values, the naturally occurring Cupronickel is still about 50-80% better than your basic non-modernized bronze. Both of these alloys were already in use by the time gunpowder was invented.

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    $\begingroup$ "due to reasons magical, civilization has aversion towards metals which are above antimony in reactivity series" Nickel is above antimony in th ereactivity series so can't be used. $\endgroup$
    – Slarty
    Dec 21, 2019 at 21:51
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    $\begingroup$ @Slarty Yes, but nickel makes extremely non-reactive alloys that are more stable than antimony. IRL, we use highly toxic materials that require special handling in the process of making non-toxic materials all the time. As long as these beings exercise proper caution in the manufacturing process, the end result will be safe for them to handle. $\endgroup$
    – Nosajimiki
    Dec 21, 2019 at 23:42
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    $\begingroup$ Also, Cupronickel is naturally occuring; so, they should be able to handle it without exposing themselves to any toxic pure nickel. $\endgroup$
    – Nosajimiki
    Dec 21, 2019 at 23:44
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How about using silver? It has a similar melting point and would be subject to a degree of corrosion from sulphurous compounds as bronze is. Might need to be a little thicker as silver is not particularly strong but then again bronze isn't that strong itslef and at least silver is a very good conductor of heat.

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    $\begingroup$ gun bronze is a LOT stronger than silver. especially in the relevant metrics. $\endgroup$
    – John
    Dec 21, 2019 at 17:37
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    $\begingroup$ Bronze is ~50%-550% tougher than pure silver depending on what quality bronze you are talking about. Silver is also 18% more dense; so, you'd need to make a barrel ~80% heavier just to compete with low grade bronze. There are some silver alloys you could probably make a decent gun barrel out of, but they are not going to be more corrosion resistant than antimony. $\endgroup$
    – Nosajimiki
    Dec 21, 2019 at 21:14
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The copper/silver eutectic alloy (28% copper and 72% silver) has a yield strength of about 40k psi. Compare this with eg the 60k psi yield strength of 4140, the most common modern barrel steel, and the eutectic would be very suitable, especially if we are talking about comparatively low pressure black powder weapons.

It's not great at dealing with heat, so rates of fire should be kept slow but not painfully so - three or four rounds a minute for a rifle or musket would be OK, but no sustained fully automatic fire.

I don't know enough about cannon to give a rate of fire, but it is 8 times as thermally conductive as steel and five times as conductive as bronze, so if cooled with water I'd guess the sustained rate of fire would probably be as fast as you can muzzle-load it. That's a guess, I'd do tests first if I had to fire it, but it should be ballpark.

Barrel wear could be an issue.

There are other silver/copper alloys which would be usable, like coin silver (90% silver, 10% copper) or even sterling silver, and some with less silver (eg 55%), but the eutectic would be best if cost was not an issue.

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Tungsten would be a good choice, but it is rare. Other metals like copper, silver and gold would be too soft. There are alloys, but they require metals that are more reactive.

Instead of guns, they might use more rockets instead. Not as efficient, but you don't get the high pressures you do with a gun.

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  • $\begingroup$ I don't think tungsten satisfies the OP's workability criteria. Can't even hold the stuff even if you can get it into molten form $\endgroup$
    – DKNguyen
    Feb 7, 2023 at 1:21

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