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Hand Cannon: The Build Part III

Part II of this build was all about the grips. That was fun, but it's now time to get into the core of this revolver - the electronics.

There are two main electrical components of this build, a flashlight and a shot counter. The flashlight is easy to add. The round counter is not.

It turns out that no ones makes an off-the-shelf futuristic laser revolver round counter.... I know, shocking. That means I have to build one and it has to be small enough to not make this revolver ridiculously heavy.

So here's the plan, take this electronic finger counter...

Futuristic Laser Revolver Round Counter

and wire up all the following such that when the cylinder on the laser colt cycles, the solenoid pushes the button on counter increasing the count by 1.

Futuristic Laser Revolver Round Counter

The elements of the image above are:

  1. Top left - simple pen light with a micro USB charger plugged in

  2. Top right - 4.5v DC solenoid

  3. Bottom left - Micro momentary roller switch

  4. Bottom right - 5000mAh portable charger to power the whole thing

Below is a video showing how it works. I'm pressing the roller switch off camera, which causes the solenoid to fire. Imagine the finger counter right in front of the solenoid.

Note - the flashlight is not wired into the switch, just the portable charger as a backup power source.

With the wiring setup working, I started the process of mounting it to the gun. First to get mounted was the roller switch. This needs to be right up against the cylinder with the roller resting open (off) in the front of one of the ammo tube holes the cylinder. In the image below you can see how I secured the roller switch to the handguard and the roller resting against the front of the cylinder.

Futuristic Laser Revolver Round Counter

Then, I needed to mount the portable charger, solenoid, and counter. I used some glue, clear tubing, and a couple metal brackets to make the three items a semi-solid single piece. Then I started cutting up the front of the handguard to make whole thing fit. Below are some pictures of the setup and my attempts to make it fit inside the handguard.

Futuristic Laser Revolver Round Counter
The round counter setup.

Futuristic Laser Revolver Round Counter
In situ about where I'd like it to fit in the handguard.

Futuristic Laser Revolver Round Counter
Opening up the handguard to fit the electronics.

Futuristic Laser Revolver Round Counter
Definitely not going to fit.

After many hours of handguard cutting and reorienting the components it was clear that this setup is not going to work. There are two main problems:

  1. The setup is both large and fragile. This means it really needs to be secured and protected by the handguard - something that isn't going to happen because its so big

  2. The solenoid & finger counter connection is very tenuous and cannot be relied upon in the shop, let alone on the set of a sci-fi action show

Time for a redesign.

The plan for the redesign is to use a digital pulse counter instead of the solenoid and finger counter combo. Although the pulse counter is larger than the solenoid and finger counter combo, it's a single item that will be easier to secure to the revolver, and is less prone to error.

Stay tuned to see how attempt #2 goes.

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