The teleportation technology hasn't been invented yet, except by another character in the story that is an ally of the hero. The hero has his own personal mad scientist buddy. (...) Think of the network as an underground type system. Designed for and utilized exclusively by the Hero.
So, let's start on the assumption that the network is privately used, built, and maintained the hero et al. and largely unknown to the rest of the world.
Let me get this idea out there: Mommy, mommy, there is strange machine in the park... arghh! News report: Child found dead by presumed energy beam from a mysterious machine discovered in the park, a S.W.A.T team is on the way to dismantle the aparatus.
The idea of an underground network for teleportation is similar in logistic to a wireless mesh network. But people don't agree on a creating a single roaming WiFi with their routers. Instead each network has its own id and password, even if setting a single configuration would give WiFi internet to everybody virtually everywhere and virtually free. Yeah, privacy and "I'm paying this bill" are the main issues.
Of course hero et al. are not convincing people to do this, instead they are leaving strange machines in random spots on the city.
The mad scientist is insane or is crazy rich:
- The mad scientist buddy is not only mad, he is also rich. He has a lot of properties accross the city where this kind of stuff can sit legally without much problem. This also explain how he was able to do the research and development required to get a working teleportation device, and also explains who is manufacturing all the bullets that get teleported to the hero and paying for the maintenance of the network.
- The mad scientist buddy has little regard for the law. In fact, he doesn't care about private property... this machines end up in somebody's roof, the tree on another person's backyard, and at the end of some dark alley. They take their electricity from somebody's connection. The machines are low quality, and tend to fail. Who said repair? Better replace and scrap the old one for part - there ain't money for more. The teleported bullets are probably stolen. And when those machines start to pop on the news, the mad scientist buddy may find the desire to teleport himself out of town.
Are there any wireless networks in operation already? Because it would be much more convenient if you could send instructions to the teleportation machines by - for example - the cell phone network.
The purpose of the network is to minimize the distance that the signal has to travel. That is, to minimize attenuation, and therefore allow you to operate with less energy. If that applies to teleportation (and why wouldn't) then you want to teleport the bullets from the nearest node.
The gun needs to communicate to the network. This is either done directly, in which case the node that gets the strongest signal is the appropriate. Or indirectly (with a third party network) in which case the gun reports its position and the nodes negotiate which one sends the bullets.
That implies that hero et al. needs to supply bullets to each node. Given that each node is able to teleport bullets and under the assumption that energy is a solved problem, you could feed them in any node and have them be teleported to the nodes that need them.
Then, if the nearest node to the hero has run out of bullets, it has to request them to the nearby nodes, which will teleport to them on demand. This adds a delay to teleportation.
Since this network is dedicated to a single type of thing only. And we are working under the idea that teleportation requires a receiver. There are is an optimization to be done: Pre-program the receivers to shape the particles that are received in a known way. This saves you sending the information of each object; they are - for all uses and purposes - identical. This implies that you don't need to pre-manufacture the objects, you just need the material.
A second optimization can be done by using mold if what you are sending is made of a single material and a very simple structure. There is a solution for that on Daerdemandt's answer under "Don't use gunpowder". Daerdemandt suggest a railgun, that would work in this scenario. The drawback is that even a 2% efficiency coilgun is only deadly at point-blank range.
So, the hero has a this backpack where he has the receiver that get the material, prints the bullets and then fed to the guns via a belt-like system attached to his arms (or even implanted?).
And why do you need teleportation anyway? You can have thousands of railgun projectiles in the backpack.
Of course, you want actual bullets. The mad scientist is actually insane, and doesn't care about economy.
So, you need copper for the jacket, and lead for the core of the bullet. You also need brass for the cartridge case and of course gunpowder. The actual manufacturing work is done by pressure not by heating or molding.
There is a problem: you are building gunpowder with a highly energetic process. Boom (actually it will burn, not explode, as you would only have a small charge and it ain't under pressure, but "boom" is more dramatic). The workaround seems to be to mix the gunpowder on site, and then assamble the bullet. For that the backpack needs moving parts.
And that is disregarding the problem of how teleportation actually works. Which you can see in my original answer below.
Instead I will suggest an alternative: you can build a laser rifle with an array of laser LED, "beam combiners" and a two or three lens system to get the most of it. The problem is the energy, but if we say that you have a car battery in your backpack and you are using 80% efficient lasers, your output is around 380W (that's an array of about 500 LEDs, so the thing is more of a bazooka in shape and size). Regardless, the thing cooks like a toaster oven.
This kind of technology would have too many implications. For starter, you will not only be able to deliver bullets, but drugs, food, etc... And the enemies of your hero would be able to.
My working idea in which to do this is to setup an ever growing network of transceivers throughout his city that triangulate the position of the guns so that the teleportation can take place accurately.
And what about interference in the triangulation signal so your hero can't get bullets? - As for scientific theory, well, non-grounded in reality.
Let's consider how teleportation works:
- It may work by scanning the
victim object, killing it disintegrating it, sending the particles, and reassembling them on the other side. This requires a wired connection or a high energy directional signal (aka. a energy beam) that goes form the source to the destination, and probably a complicated chamber where the reconstruction happens.
- Instead of the chamber, try manipulating individual particles at large distance. So, you don't only send the particles, you use a giant laser to move them around. Disregarding the problem of focusing the laser, you now need much more energy.
- Why do we have to send the particles that made the original? Instead we could just send the information and have it be constructed (3D printed) from materials at the destination. Now sending the information is not a problem, but the destination needs to have material to build the object. Of course, you aren't disintegrating the original anymore.
- Use quantum entanglement to push the target particles into the correct state. Ern... no, quantum entanglement doesn’t work that way. You need to have the particles interact for them to get entangled. So you either sending entangled particles to the destination or the destination have to carry pre-entangled particles. By the no-cloning theorem the original is destroyed to extract the information that is then transmitted by the entangled particles. So, it is the same situation as before, quantum entanglement bought you nothing.
- Use portals, I mean wormholes, well, Nolo covered this one.
If you are going to disintegrate something, you need enough energy to move all of its particles, over whatever distance you want to move them. And you want to do it as fast as possible... light speed fast. But you can't because what you want to move has some mass. In fact, you think you are building a teleportation machine, but you are building a particle-beam weapon. Just shoot at the enemy.
Let's assume that teleportation just works:
- Accidents happen, like any means of transportation there relies on machinery (ie. everything except walking barefoot) depends on that machinery working correctly. It is expected that there would be malfunctions from time to time.
- Would it work on machines? If I can deploy a bullet, I can deploy a combat robot. Oh, my setting doesn't have robots - I wonder how technology evolved then. The evident uses of teleportation in the battle field include deploying troops, supplies, ammo, and weapons.
- The energy for the teleportation is not free; the hero could be required by law to pay for this service. In fact, similar technology could be useable to supply electricity or even water. If we go with the idea of the network, the infrastructure can't be built on teleportation; this means that teleportation is expensive. Teleporting something would be at least as expensive as the energy bill for the equivalent energy of the teleported mass... plus inflation (the network needs maintenance, also it is expanding, and somebody pays for that).
- At some point teleporting something is too expensive - because it is too large, or because the distance is too long - and then conventional transportation is used.
- The fact that the network is growing suggest that teleporting is a profitable business, so I would expect various commercial or industrial companies taking advantage of teleportation. I these companies consider teleportation cheap; it probably means that the region has other infrastructure problems (maybe it is an isolated location). On the other hand, these companies may be providing instantaneous delivery at high fees – and it is popular. I wonder for what kind of things people may be willing to pay crazy money for the “right now” option, also, in what does people work to have money for this to be popular?
- The above implies that "heroing" is has good revenue. I would expect it to be at least fairly common. It would be an activity similar to bounty hunting. Alternatively, the hero is not operating under the law.
- The bad guys don't pay (either they are criminal, or they are the government), they take advantage of the network, they make it so it won't give more bullets to the hero... or perhaps a bullet on the chest.
I was typing while the linked answers came up.