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Backyard Ballistics

backyard-ballistics.com

67 pointsthetopher26 comments

I made the potato cannon from this book as a teenager. It was made of a PVC chamber for the propellant and a narrower ~potato-sized PVC pipe with the end filed to be sharp so that a potato would be trimmed down to create a potato slug with no air gaps around it.

The propellant was hairspray. You'd unscrew a threaded PVC end-cap from the back of the cannon, spray the hairspray into it, screw the cap back on, and ignite with a flint striker from the outside.

It was a really cool device.

I built this exact same thing as a teenager. The “thoomp” was very satisfying. Living in an area with a lot of sage brush made me too scared to try the Cincinnati Fire Kite, though.

Tried that one as a kid when the fog was really thick. Unfortunately couldn't get it to do much more than fall slowly.

Made something similar without a book...

The best was breach loading a racket ball that wouldn't quite fit into the barrel, but would get stuck enough to not fall away when presented forcefully from the larger combustion chamber side.

They flew way farther than potatoes, and exited the barrel with deformations in their ball shape from not quite fitting, making the flight path all sorts of erratic for the first hundred feet or so.

We used to take it to a nearby park and get kids to catch and return fly balls by shooting ~vertically for them. You couldn't even see the ball for a good chunk of the flight, good times. Prolly get arrested for such a thing today.

Prolly depends more on where you are than when you are.

In a rural area, you're still looking at a pat on the back instead of handcuffs, in the unlikely event that an authority figure notices.

In a suburban area, you get cops asking if you could please stop detonating vegetables near your nosy neighbor's property.

In a dense city, you might be lucky if you can avoid being shot to death after the first few explosions.

I picked up a copy of this a while back and placed it in one of bookshelves to see how long it took my 12 year old to find it. Found it in his room about two weeks later..

I would recommend reading up on what the ATF considers a "destructive device" or "any other weapon" before home building any cannons or similar things.

https://www.google.com/search?client=firefox-b-d&q=atf+defin...

An ignorant but technically motivated person can also "accidentally" build an NFA form 1 or form 4 firearm by making a short barrelled rifle without the appropriate tax stamp, just by combining pieces together. Or by doing something like putting a vertical foregrip on something that is legally a pistol. Or by making a home-made silencer. And so on.

https://www.atf.gov/firearms/firearms-guides-importation-ver...

> Any type of weapon by whatever name known which will, or which may readily be converted to expel a projectile, by the action of an explosive or other propellant, the barrel or barrels of which have a bore greater than one-half inch in diameter.

Hmm, guess that would technically cover potato canons? Though the exemptions include

> a device which is neither designed nor redesigned for use as a weapon

:shrug:

Only if it shoots flaming tennis balls.

I wonder if they make silencers for wet blankets :p jk

> Or by making a home-made silencer

My father made 3 of these in the 1980s for 3 different caliber pistols. We later disassembled them out of fear.

Isn't there a "homemade gun" scene that operates on the idea that a weapon whose resources are collected in a single state, and that is assembled is that state, is not subject to federal firearm restrictions? (Since many if not most federal regulations rely in the commerce clause)

I don’t know. But silencers are not guns and are outlawed federally.

They aren’t outlawed federally. They’re just subject to a $200 tax stamp.

Getting the tax stamp takes several months, unfortunately.

And you need a new stamp if you want to transfer it to another person.

The point is, the federal government does not have a delineated power to regulate firearms or silencers. When they outlaw them, they say they're regulating "interstate commerce", which is a power they are granted.

If you manufacture the silencer yourself and don't cross state lines, and the materials you used also didn't cross state lines, the federal govt can't regulate it. (Although the state can.)

I found more info: https://en.m.wikipedia.org/wiki/Privately_made_firearm

People are 3d printing Glock 19 gen3 compatible frames, the rest of the parts can be purchased with no FFL or serial number.

> I would recommend reading up on what the ATF considers a "destructive device"

Oh you pussy. You think Sam Bankman-Fried built a 20 billion dollar empire with that attitude?

"Empire" is a big word for a pyramidal tower of cards

All empires are towers of cards, with respect to some timescale.

Out planet is just a backyard ballistic, on the appropriate timescale

Would you please stop posting unsubstantive and/or flamebait comments? You've unfortunately been doing it repeatedly. It's not what this site is for, and destroys what it is for.

If you wouldn't mind reviewing https://news.ycombinator.com/newsguidelines.html and taking the intended spirit of the site more to heart, we'd be grateful.

Considering that no potato cannon uses cartridges, then I doubt that NFA applies to them?

People make bowling ball mortars from gas cylinders and those have a bore even larger than any potato cannon. Yet they are perfectly legal.

Ofc here both are illegal, as the potato cannons cannot use combustion for power.

I recently found this book in a used bookstore. I wish I had owned a copy when I was a kid. I’m thinking about giving one to my nephew, but I’m not sure what his parents would think.

There's also The Dangerous Book for Boys

This was one of my favorite books growing up

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