shooter

3 Articles

This BB Shooter Has A Spring, But Not For What You Think

June 2, 2025 by 24 Comments

[It’s on my MIND] designed a clever BB blaster featuring a four-bar linkage that prints in a single piece and requires no additional hardware. The interesting part is how it turns a trigger pull into launching a 6 mm plastic BB. There is a spring, but it only acts as a trigger return and plays no part in launching the projectile. So how does it work?

There’s a spring in this BB launcher, but it’s not used like you might expect.

The usual way something like this functions is with the trigger pulling back a striker of some kind, and putting it under tension in the process (usually with the help of a spring) then releasing it. As the striker flies forward, it smacks into a BB and launches it. We’ve seen print-in-place shooters that work this way, but that is not what is happening here.

With [It’s on my MIND]’s BB launcher, the trigger is a four-bar linkage that transforms a rearward pull of the trigger into a forward push of the striker against a BB that is gravity fed from a hopper. The tension comes from the BB’s forward motion being arrested by a physical detent as the striker pushes from behind. Once that tension passes a threshold, the BB pops past the detent and goes flying. Thanks to the mechanical advantage of the four-bar linkage, the trigger finger doesn’t need to do much work. The spring? It’s just there to reset the trigger by pushing it forward again after firing.

It’s a clever design that doesn’t require any additional hardware, and even prints in a single piece. Watch it in action in the video, embedded just below.

Continue reading “This BB Shooter Has A Spring, But Not For What You Think” →

A game board with five LEDs and a hand shining a laser pointer at it

Laser Pointer And Arduino Make A Minimalistic Shooting Game

October 18, 2021 by 7 Comments

Video games are great and all, but sometimes you just want the thrill of manipulating actual objects in addition to watching action on a screen. This must have been the reason why Nintendo’s Duck Hunt became so popular despite the simplicity of its gameplay. Prolific hacker [mircemk] similarly made a computer-plus-physical game called “Laser Shooter“, which somehow reminds us of the good old NES game.

The game is based on an Arduino Nano, to which five LEDs as well as five photoresistors (LDRs) are connected. When the game is started, the LEDs light up at random and the player has a limited time to “shoot” the corresponding LDR with a laser pointer. This time limit is decreased as the game progresses, and the game is over once the player fails to hit the target on time. The “Game Over” message is accompanied by a sad tune, but luckily no giggling dog.

Complete schematics and code are available for anyone willing to try their hand at replicating or improving this game. And no, you can’t simply sweep your laser across the five LDRs all the time, because you lose if you shoot at the wrong target. For more laser pointer-based games, try this Laser Command clone or this laser tag badge system.

Continue reading “Laser Pointer And Arduino Make A Minimalistic Shooting Game” →

Palm-Sized Gatling Gun Has 32 Mini Elastics With Your Name On Them

February 13, 2019 by 15 Comments

One thing 3D printers excel at is being able to easily create objects that would be daunting by other methods, something that also allows for rapid design iteration. That’s apparent in [Canino]’s palm-sized, gatling-style, motorized 32-elastic launcher.

The cannon has a rotary barrel driven by a small motor, and a clever sear design uses the rotation of the barrels like a worm gear. The rotating barrel has a spiral formation of hooks which anchor the stretched elastic bands. A small ramp rides that spiral gap, lifting ends of stretched bands one at a time as the assembly turns. This movement (and therefore the firing control) is done with a small continuous rotation servo. While in theory any motor would do, using a servo has the advantage of being a standardized shape, and therefore easy to integrate into the design. A video is embedded below in which you can see it work, along with some close-ups of the action.

Continue reading “Palm-Sized Gatling Gun Has 32 Mini Elastics With Your Name On Them” →