Crossbow Autococker

[mlangsdorf]

Originally Posted by Derrick_rp

Would a plastic jacket do the job? The characters have more access to plastics than metal.

For rifling and possibly as a container for shattered glass, sure. As a hardener for armor penetration, I don't think so.

Plastics are usually low density, so you need an even longer bullet to have the same amount of mass. Same with brick, that ericthered suggested: about 2/3rds the density of glass, so a 3" slug instead of a 2" slug.

I'd probably go with plastic coated concrete or brick for cheapest training rounds, plastic coated glass for general purpose rounds, and metal jacketed glass for your emergency expensive armor piercers.

The brick rounds are also probably adequate for short range - they're lighter and faster than glass rounds of the same length - but they have less effective cross sectional density and will slow down a lot faster and have shorter range. Probably won't matter within 40-50 yards, though.

[malloyd]

It also occurs to me on the original topic that if you can build an autococker that works on compressed air, it may well be lighter overall if you replace the compressed air tank with gunpowder - it's a handy enough way of generating small amounts of high pressure gas on demand.

[DanHoward]

Originally Posted by mlangsdorf

Glass isn't cheap to cast, but its probably cheaper than grinding hard stone.

You don't cast them. You should be able to make them like lead shot by dropping molten glass from the top of a tower into water. The process might also strengthen the glass by tempering it when it hits the water.

[Ulzgoroth]

Originally Posted by DanHoward

You don't cast them. You should be able to make them like lead shot by dropping molten glass from the top of a tower into water. The process might also strengthen the glass by tempering it when it hits the water.

That won't work if you're trying to generate an elongated slug.

[Culture20]

Originally Posted by DanHoward

You don't cast them. You should be able to make them like lead shot by dropping molten glass from the top of a tower into water. The process might also strengthen the glass by tempering it when it hits the water.

Water shatters molten glass as the glass hyper-cools. Glass requires a slow cool-down.

[AlexanderHowl]

There are also tens of thousands of types of glasses, but the majority of the good ones require metal contaminates (which is fine, since humans can live on the world, it has calcium, copper, iron, etc). A more interesting world would be one without anything heavier than iodine in anything but trace amounts on the surface. How would human civilization progressed without commercially viable sources of gold, lead, and uranium?

[Ulzgoroth]

Originally Posted by AlexanderHowl

There are also tens of thousands of types of glasses, but the majority of the good ones require metal contaminates (which is fine, since humans can live on the world, it has calcium, copper, iron, etc). A more interesting world would be one without anything heavier than iodine in anything but trace amounts on the surface. How would human civilization progressed without commercially viable sources of gold, lead, and uranium?

Gold is useful for a few things but critical for very few. Uranium is mostly good for exactly one thing.

Lead is pretty darn handy, to be fair, especially in the period where you don't realize you're poisoning everyone with it...

[AlexanderHowl]

Imagine the colonization of the Americas and Africa without the motivation of gold. Imagine the Cold War without uranium. While they are not useful for much, world history was shaped by the search for gold and the force of uranium.

[Ulzgoroth]

Originally Posted by AlexanderHowl

Imagine the colonization of the Americas and Africa without the motivation of gold. Imagine the Cold War without uranium. While they are not useful for much, world history was shaped by the search for gold and the force of uranium.

Silver could and did have much the same influence as gold, though not always in the same places.

And, well, yes uranium suddenly makes a splash on world affairs in TL7. OTOH (A) it doesn't need to be commercially viable and (B) 'how would human civilization have progressed' is weird phrasing for something that only mattered for the past 80 years.

[AlexanderHowl]

Without the risk of mutual destruction from nuclear weapons, the US and the USSR would have likely engaged in WW3 during the 60s, so I think that WW3 would have probably ended Western civilization even without nuclear weapons (probably 600 million to 1 billion casualties). I think that the availability of uranium allowed Western civilization to continue because the implicit threat of nuclear annihilation forces nuclear powers to engage in proxy wars rather than direct wars.