CompBullets are claimed to go faster than regular bullets, due to vents that have been mac...

Competition shooters like their bullets to fly as fast (and thus straight) as possible, and they try to keep recoil to a minimum. Italian ammunition-maker CompBullet produces a series of bullets of the same name, which are claimed to both go faster than normal ammo, and produce less recoil. The secret? The bullets have go-faster holes in them.

Available in several calibers, the copper alloy bullets have a main cavity in the base, with multiple “vents” machined into their sides. These reportedly serve several purposes.

First of all, when the gun is fired, the vents supposedly allow the propellant gases to go through the sides of the bullet, providing lubrication between it and the inside of the gun’s barrel.

CompBullets are claimed to go faster than regular bullets, due to vents that have been mac...

As the bullet exits the gun, the gases symmetrically shoot sideways out of the vents. This – so we’re told – creates a “muzzle brake” effect. A muzzle brake is a device fitted to the end of a gun’s barrel, that redirects the gases as they leave the gun, to offset the recoil effect. The vents in the CompBullets apparently serve the same purpose.

At the same time, the gases shooting out of the vents are also said to create a rocket-like effect, increasing the bullet’s velocity. All of you physicists are welcome to weigh in on this one, but it’s hard to say if gases exiting the sides of a bullet would really cause it to travel any faster than gases that were limited to pushing on it from behind.

Additionally, CompBullets are claimed to produce less muzzle flash and less smoke. If nothing else, all those holes probably make them lighter than regular bullets, to boot.


Henry Sapiecha

The Mouse-Box includes a 1.4GHz CPU and 128GB of storage

We’ve seen plenty of compact PCs in the past, but few as tiny as the Mouse-Box. This new invention from a team of Polish engineers packs a fully-functioning computer into a mouse that you can hold in your hand. All you need to add is a screen and a keyboard and you’re ready to start work, get online or launch a presentation. The Mouse-Box is currently at the prototype stage and its makers are looking for funding to bring it to production.

Its level of portability is a huge selling point, because if you’re going somewhere with a monitor or projector available, then all you need is a pocket rather than a laptop bag.

Inside the mouse you get a 1.4GHz dual-core ARM CPU, 128GB of flash storage, two USB 3.0 ports, a micro-HDMI output and Wi-Fi connectivity — not bad for something so tiny. There’s not much room for your programs and files, but as Chromebooks have proved, huge amounts of local storage aren’t always necessary for something that you take on the road. The group is also working on a matching mousepad that can double as a charger while you’re using the Mouse-Box.

A micro-HDMI connector is included to attach the Mouse-Box to a display

If you want to just use it as a normal mouse, then that’s fine too. You could take it into work and then switch between your work PC and the Mouse-Box with a button press, for example.

The prototype is fully functional, but the Mouse-Box team is looking for a manufacturing partner to be able to produce the device commercially. Given its specifications, it’s likely that the finished product would run a lightweight OS such as ChromeOS or Linux, but no further details have been divulged just yet. Another unknown is the price, though the developers have gone on record as saying the Mouse-Box will be available cheaply and across the world, funding permitting.

Is this something you’d back on Kickstarter or Indiegogo? If so, the Mouse-Box inventors would love you to share their video, embedded below.


Henry Sapiecha

The Science Behind Real-Life Invisibility Cloaks

Harry Potter makes it look so easy, but rendering objects invisible is a tricky business, dependent on slights-of-hand and perfectly angled mirrors.

Invisibility — or the concept of turning an object completely and undetectably transparent — is the stuff of make-believe, typically reserved for authors of Medieval fantasy, walls in video games and movies featuring precocious kid wizards with South Londoner accents. Yet it is not all magic rings and fairy dust.

Lately cloaks of invisibility have become a topic of serious scientific discussion and, at least in theory, something scientists can bring about. What we once thought was imaginary may simply be really hard to do.


“What I mean by cloaking an object is that the object becomes fully transparent to visible light, not merely camouflaging or hiding objects,” explains Andrea Alù, an associate professor of engineering at the University of Texas, where he researches the strange behaviors of radio waves and light.

Alù says are plenty of tricks that give the illusion that something is invisible.

Scientists at the University of Rochester, for instance, have developed special lenses that, when looked into, allow professionals like surgeons to gaze through the back of their hands while performing operations, sort of like x-ray vision goggles in real life. In actuality, the illusion is created by an elaborate system of mirrors positioned just right.


In 2012, Mercedes funded a camouflage technology that in essence hid vehicles in plain sight. It used cameras to capture objects passing behind the car and projected them on a screen placed in front of the car, so that the car appeared to be clear as glass.


Alù says this is similar to how nautical animals like mimic octopuses disguise themselves in nature, scanning the seabed and projecting the colors and patterns on their skin. Impressive, yes, but it is still a sleight of hand (or tentacle, as it were).

Instead of optical illusions, Alù is proposing a cloaking material with unusual properties that makes it genuinely invisible. Imagine wearing a hypothetical invisible body suit, which would cast no shadow as light gracefully rolled around your legs and hips and body instead of bouncing off of them.

Light is not supposed to work like this.

“The only way to go around our fundamental bounds is to use active cloaks,” says Alù.

This gets complicated, but an active cloak involves curious man-made dyes and molecules known as metamaterials, which send light on a detour around an object. Think of it as taking the bypass instead of driving down the main drag.


This tactic would effectively render things invisible, but it has some truly paradoxical side effects. Since it would take longer for light to travel all the way around an object — let’s say, your totally incognito invisible house — instead of passing straight through it, there would be a bizarre lag effect, where time would seem to progress at different rates.

If, for instance, you were standing on the curb in front of your house and facing it, the area surrounding your invisible house would look normal. Clouds would blow by and trees would sway on their regular schedule.

However, within the transparent rectangle where your cloaked and invisible house was located, time would appear to be moving noticeably slower, delayed by perhaps more than a few seconds.

“Essentially we’re fighting some fundamental laws of physics,” Alù says, and for that reason making objects legitimately see-thru will be extremely difficult. “You can do it. We do it for radio waves. But it is a really long shot,” he says.

So why aren’t we all out prowling invisibly now?

Well, for the time being, metamaterials (or fluoresce, in scientific terms) only work for a very limited amount time. In laboratories today, only objects no larger than a flea or a speck of dust can be turned invisible.

It may take a hundred years, says Alù, but there may come a day when we can hide inside our invisibility cloak.

Then, science can get to work on levitating broomsticks.

Light smoke via Sergio Alvarez; Invisible Man via Andrew GustarInvisible truck via Matt Green; Invisible Man 2 via Eric Tastad; Invisible woman via splityarn.

In this series, we explore how light illuminates, enlivens and even accelerates many aspects of our lives as scientists and artists discover new uses and meaning for the Light in Our Lives.


Henry Sapiecha