[Sam] sent in a coil gun revolver – a feature we’ve never seen on a coil gun build before. The gun is based on a cheap toy revolver and is powered by a 9 Volt battery connected to an “electrified fly swatter tennis racquet” instead of the usual disposable camera build.

The revolver mechanism isn’t perfect – [Sam] has to advance the chamber with his thumb while the capacitor is recharging. This is only because of the mechanics of the plastic toy his gun is based on, though. He figures a small motor could do the work for him, but he’ll be forgoing that project to work on the MK II version.

Most of the coil gun builds on Hack A Day have been muzzle or breech loaders, so with [Sam]‘s revolver we’re probably seeing the evolution of firearms mirrored in coil gun advancements. Does anyone want to take a guess and predict when we’ll see the equivalent of a this .50 caliber beast?. [Sam] says his next project is going to be a rifle, so he might have his work cut out for him.

Here at Hackaday, we’re all about repurposing old items you no longer use. Reader [Liquider] wrote in to share his latest creation, a coil gun built from an old Airsoft pistol.

He removed a handful of components from the pistol and installed a 800 uF/300V capacitor inside the grip. A small storage compartment was added under the barrel, which houses the AA battery he uses to drive the circuit. A modified reloading mechanism makes it easy to drop a metal projectile right in front of the coil before firing.

Once the pistol is charged up, a switch installed behind the trigger discharges the cap, creating a magnetic pulse that accelerates the metal projectile forward. [Liquider] estimates that the kinetic energy produced by the coil is 0.1 Joules, which fires of the slug at a reasonable speed.

Continue reading to see a quick video demo of the pistol in action.

[Daniel Eindhoven] put together this 11,344 Joule capacitor bank that he says would be perfect for weapons such as a rail gun, coil gun, or electrothermal-chemical gun. He machined a couple of aluminum plates to act as a positive and negative bus. The two are separated by a denuded sheet of PCB (making us wonder how he got the copper to peel off like that). Once charged there’s the little problem of how to discharge the system without getting bit, which [Daniel] solved by building a pneumatic switch. We didn’t find the test-fire footage very interesting but we did embed the demonstration of his switch after the break.

[Thanks Kurt via Hacked Gadgets]

Some readers may remember [Paul] from his project Jak, the blackjack robot; but his interests have moved toward coil gun creation. Maggy, his latest weapon, may not be the prettiest of coil gun we’ve seen, or the most environmentally friendly, but does look to be promising. Featuring a triple stage, logic based accelerator instead of the typical single stage, it can fire a 10 gram projectile (theoretically) up to 85 km/h! Check out how he’s gone from a single pistol to his current monster on his site, and a video of his work in progress after the jump.

One of the best parts of building a coil gun is seeing just how fast you can get that slug to move through the air. [Daniel] built this speed meter to be able to see exactly that. It is comprised of two optical sensors, one at each end of a barrel. As the projectile passes them, its speed is calculated using an Atmega16. Since the distance between the sensors is pre determined, its only some simple math to figure out the speed of an object passing between them. The result is then displayed on a nice looking blue LCD.

If the blue accent lighting and acrylic stylings look familiar, that’s because we’ve seen [Daniel] before. He’s the one that built the portable coil pistol.

[via HackedGadgets]

TechEBlog has posted a few pictures of a student constructed coil gun. It’s bolt-action and includes a six round magazine. The gun only has a single stage to accelerate the projectile. While not as impressive as the portable coil pistol, it’s still more fun than most shop projects we’ve seen. You can find a video of the device below.

[via Gizmodo]

[Daniel] had to have runaway in his mind when he built this coil gun. It’s hand held, holds 14 42 gram rounds and can propel them at speeds of 110km/h. Of course when it is battery powered, you have a 90 second warm up time between shots. It can also be used while plugged into a wall socket, which reduces the charge time to roughly 3 seconds. Great job [Daniel].

[via engadget]

[thecapacity] sent us his iobridge project where he controls a coil gun with a Wiimote. To make the coil gun, he took apart an office golf putter that had a ball return.  The mechanism to return the ball is a metal cylinder that is moved magnetically. He simply replaced the cylinder with a smaller diameter piece of metal to create the gun.   His computer monitors the Wiimote axis changes and sends them to the ioBridge. The unit could be located anywhere, but without a camera on it, he’ll have a hard time aiming. There’s a video of it working after the break.

[rocketman221] wrote up one of the simplest ways to build a high voltage power supply. This one in particular was used on his coilgun. Instead of building a custom circuit, he’s using flash charging boards from disposable cameras. Six 450V 470uF caps are wired in parallel to make up the bank. Two of the charger boards are wired to one switch to initiate the charging process. Four additional boards are wired two a second switch for the second charging stage. The part cost on this is incredibly cheap and it only requires a 3.3V input to reach 450V. The writeup has plenty of warnings about the dangers of high voltage; you need to clean off all flux residue to prevent arcing across the circuit boards. Embedded below is a video of the bank being discharged through several objects.

The Leyden jar capacitor posted the other day fails to compare to what [FastMHz], one of the members over at the 4HV.org forums, has been busy building, a 24kj capacitor discharge bank. This capacitor bank will be configured for 4500v @ 2400uF and can be charged up slowly using microwave oven transformers. It can then release all its stored energy in under a millisecond through a triggered spark gap. This allows for some pretty big sparks as seen in this video, we are not sure about the laughing in the video maybe the power has gone to his head?

A bank like this can be used for a railgun, induction launcher, or exploding things in general. Coin shrinking and can crushing require much quicker discharge rates than what electrolytic capacitors are really capable of, and generally perform better with large pulse capacitors, however it will be interesting to see the final use for this potential energy.