Remote Control Bullets

Question

So in my world there is an army of snipers (bad guys). I want them to have remote control bullets. I want the bullets to be able to lock-on to a target without using a laser. So like this:

but without the laser. I want them to be able to fly long distances. How would the bullets locate the person? and how could they be stopped by the heros? This is in the future!

Bullet lock-on ideas

Facial recognition (won't work since they might look away)

Ideas on how to stop it

Jamming communication between gun and bullet (gun controls bullet)

Answer 1

What you are describing is effectively a guided missile and not a bullet per se. There are forms of artillery ammunition which could perform feats similar to what you describe. The Excalibur artillery round will attempt to hit a predetermined point programmed into its GPS system, using GPS signals to navigate and small fins to guide it onto the target. The Bofors STRIX 120mm mortar shell has an active infrared seeker which allows the shell to autonomously move to the target (the around was designed to be used against tanks). An earlier idea was the 81mm Merlin mortar shell, which had a millimetric wave radar to guide to towards a target.

So the idea that a ballistic round can mount a seeker head or GPS and direct itself towards a target is hardly far fetched. The real issue is the bullet from a firearm is far smaller than an artillery shell, so the room for the seeker mechanism, computer, actuators for the guidance system and a power source becomes extremely limited. This would make manufacturing such a system incredibly challenging, and each round would be quite expensive (a true "silver bullet", so to speak).

The other issue is the kinetic energy the round will deliver will be far less than a "dumb" bullet. This is mostly to do with the cross sectional density of the round. A standard NATO bullet like the SS-109 5.56X45 small arms round has a steel "penetrator" surrounded by a copper jacket which provides the aerodynamic shale and lubricates the round as it passes down the barrel. A "smart" round will have a lot of tiny machines and computer parts packed in the same volume, so weigh far less than the equivalent dumb round. Less mass means less momentum (the bullet will slow down much more quickly, somewhat like the way a ping pong ball will slow down much faster than a golf ball if thrown at the same speed). Even after taking that into account, when the bullet strikes, it will more likely shatter than penetrate, particularly if the target is wearing armour or protected by something solid (say a car door or the corner of a building).

So your bad guys will have ridiculously expensive rounds with absurdly short ranges, capable of causing injuries but not reliably killing the target.

If you really want to have expensive mayhem, have the killers mount a 7.62mm minigun on their car and hose down the entire area where the target is. It is much more reliable and probably far more satisfying for the shooter as well (the target is unavailable for comment).

Answer 2

Assuming handwaved magic bullets that can adjust their path regardless of where the gun is pointed.

Lasers are the best option. There are other location and directional methods, but pretty much every single one of them requires extensive electronics in the bullet - decreasing its power by making it larger AND lighter. Also, expensive. Additionally, they require communication between the bullet and gun to coordinate. There are very, very few methods of communication for such an object that would not instantly spotlight the gun and, potentially, the bullet itself.

Torpedoes are often guided by wires to the ship - But you can't do this with a bullet because the wire would snap due to the incredible forces and speeds. Also, a wire attached to a bullet would do such wonderful things to its stability.

Theoretically, you could have a GPS unit inside the gun, along with an accelerometer and magnetometer. This would let you know exactly where the gun is and exactly where it is pointed. Put them in the bullet as well, and you know the same for the bullet and can guide it - Via radio waves. As mentioned before, this spotlights the firer and the bullet. Additionally, one further thing is needed for proper directional control - Distance from the gun to the target. There are a few ways to do this - But they're generally inaccurate at the ranges required. You could use radar but... Well, that's even MORE of a spotlight. Also, it's probably pretty large, too. The best solution is a laser rangefinder.

And if you're using a laser, you might as well use it right.

Answer 3

There are legit near future / known tech answers on here already. How about some scifi that is more outré?

The bullets steer with fins by assessing the probability of the future in which the bullet hits its target. These bullets can see possible future worlds and adjust actions so as to maximize the desired future world. Probabilities change on the fly (so to speak). The limit of the future vision of a bullet is the flight time of that bullet.

This is like the limited future vision of Nick Cage's character in Next. Here he walks up to a gunman by assessing which motions on his part lead to a future where the shot does not hit him.

https://www.youtube.com/watch?annotation_id=annotation_74546&feature=iv&list=PLCDA5EF834647EEED&src_vid=lufECeWtN34&v=RC5ZiK6o7uQ

If homing bullets are just a prop in a space cowboy adventure then maybe this is overkill. In a high SFD story, these things could be poorly understood artifacts which were discovered and are being used as bullets by the space cowboys. But what else can you accomplish with a "bullet" that has this ability?