I’m reading an SF book in which people can “step” across to parallel versions of earth, but for some obscure reason, metallic iron cannot make the transition and is left behind. Iron atoms bound up into other molecules is fine, such as the iron in our haemoglobin, but metallic iron (and therefore steel) are out.
So with this premise in mind, is it possible to build a working firearm that has absolutely *zero *iron or steel parts? Cost aside, could the necessary elements instead be made out of something like titanium?
Furthermore, assuming technology advanced enough to travel through alternate dimensions it wouldn’t be entirely unreasonable to assume the discovery/invention of some sort of exotic material that exhibits whatever qualities the author desires. It all depends upon how “hard” the scifi is.
The parallel earths in the novel are virtually identical to our own and conform to the same laws of physics. The only major difference is that none of them have any humans on them. So exotic materials are out, but all of the planets’ iron ore lies untapped, ready for mining and smelting etc…
The problem lies in taking anything “across” in the first place.
It’s been done before. Early cannon were made from Bronze and made in a similar manner to casting bells (in fact, bellmakers were the first cannonmakers).
So you could quite easily make a matchlock muzzle-loading firearm with a bronze barrel, lockplate, and serpentine, and high-tension plastics for the springs needed to make the serpentine engage with the touch-hole after the trigger is pulled.
Exactly the sort of excellent, informative answer I was looking for. Would something more modern than a matchlock be feasible, such as a repeating rifle of any kind? Wouldn’t brass be too soft for prolonged use?
With respect to modern firearms the only real issue would probably be making springs without steel. You’d have to settle for lower powered cartridges and/or increased wear on the weapon. A pump action shotgun seems reasonable as long as the spring issue can be worked out or the user doesn’t mind swapping Martini Enfield’s plastic solution whenever it wears out.
If anything but iron goes, I’m sure there are alternatives to steel- just that they’re going to be expensive and difficult to fabricate. Even discounting the stuff that’s too reactive to be useful like sodium or too soft like gold, there are still a score of candidates.
But you’re probably not going to get away with a real Ar-15 clone or anything firing high velocity, jacketed ammunition. I have no math to back up that claim, but I expect that it would be wise to stay with lead bullets and relatively low velocities. .45ACP seems perfect for that application in a handgun.
It could certainly be done; they just never bothered IRL because by the time rifling was invented, gun barrels were made of iron or steel.
Incidentally, Confederate-made revolvers during the US Civil War used a lot of brass (and, I believe, bronze) components. They weren’t really up to prolonged use, from what I gather, but you could certainly make something like a Navy Colt without using iron or steel as long as you didn’t expect it to last for a long time.
Just restricting the use of iron doesn’t make the fabrication of a modern firearm all that difficult. If you want a real challenge you’ll have to eliminate the use of all metals.
There is a number of copper, nickel, and titanium based alloys that can readily replace steel. So any kind of firearm could be made completely without iron.
It’s possible to build a cannon out of duct tape, so there is no reason you couldn’t make a rifle. Unlikely to be accurate or practical, but it would work.
Taurus has made several pistols out of non-ferrous metals. Cite. I can even recall one model (at least, there may have been more) made of scandium. But note this from the article:
So if you replace those operating parts with a metal other than hardened steel, you’ll probably be sacrificing durability.
A bamboo barrel, reinforced with a rawhide wrapping applied wet etc. would make a serviceable, (crappy) low-power firearm without any metal in it. That’s how some of the early Chinese guns were made.