Spud Gun

A spud gun is a form of potato shooter that is made of ABS (or PVC, but ABS is recommended.) pipe. A friend of a guy named John Rich made the designs of the spud gun. John Rich put up a website called "Backyard Ballistics" in 1995 in the city of Houston, Texas. He probably did this for the purposes of fun. (Note: I am about to tell you how to make one of these things. Do not use this for any purpose other than fun. Do not point this at anyone or anything. Do not even build one. You could become seriously injured or killed!)


How to make a spud gun



  1. * Cut off a 14-inch section of the 3-inch diameter pipe.
  2. Glue the bushing into one side of the 3-inch coupling.
  3. Glue the other side of the coupling to the 14-inch part you cut off in step one.
  4. Glue the threaded coupling to the other end of the 14-inch part.
  5. * Cut a three-foot part of the two-inch diameter pipe. It will be a barrel.
  6. * Taper the end of the barrel, which will serve as a muzzle.
  7. * Install Coleman sparker in end cap.
  8. Let glue dry.
  9. Make ramrod. It should be 4 feet long. Make mark in ramrod 2 feet 8 inches down ramrod.

To fire: Remove end cap. Ram in potato to mark. Put in 2 seconds of Aqua Net hair spray. Aim and twist igniter knob.

* Power tools required.

Power tool section

Step 1: Use a reciprocating saw to cut off the 14-inch section.

Step 5: Use a reciprocating saw to cut off the 3-foot section.

Step 6: Use a belt sander to taper the end of the barrel.

Step 7: Use a power drill to make a hole to install the Coleman sparker.

My "Ballistic" trip to the beach


You want to do the first shot, Bill?"


Yes, there I was, at the beach, with my Dad holding something that looked like a primitive bazooka in his hand. We had told the people nearby what we were doing. They’re general response:


What, exactly, were we doing?

We had brought our project, a spud gun. We, afraid someone would call the cops on us, figured we’d have to find the least popular beach. The less people there, the fewer people who would think this was illegal. SSSS! went the Aqua Net as we sprayed it in.

One spark. That was all I needed to blow out the potato. I twisted the sparker, which sparked the flint and BOOM! Out shot the potato with enough force to puncture newspaper.

"Well, what do you know? Tartaglia was right." I thought absently. "It does go in a curved path."

(Note: One of these shots went 56.875 feet.)

Nicollo Fontana Tartaglia’s New Science of Ballistics

The science of ballistics is the study of flying projectiles.




The ‘new science’ of ballistics was published in 1537 when Niccollo Tartagila described a quadrant, which was an instrument inserted into the gun to measure the angle of the barrel. The angle of the barrel was important because it would allow the projectile to go higher and farther. Ballistics is a science to predict the angle for a projectile to hit a target.


Ballistics was used for weaponry because it could get projectiles to go farther. Projectiles went farther because you knew how much to raise the angle of the gun.


Thanks to Niccollo Tartagila we know that a gun’s projectile goes in a curved path. Figure 3 is a picture from Niccollo’s book, "Nova Scienta."








Tartaglia was not the family name! He got that nickname because, after he got injured in a battle, he stammered. The nickname Tartaglia means ’to stammer’. Tartaglia also invented the math use of parenthesis. Tartaglia was born in Brescia, Italy.







Projectiles Used as Weapons 1450-1550

The Rocket

The beginning of ballistics began in China where fireworks were popular things. Someone occasionally accidentally left one side open and WHOOSH!

Up the rocket would go into the air.


The Longbow

A longbow was the most deadly weapon in medieval times. It was 6 feet long and worked best when fired from a mountain. It was usually made from yew wood.

The Cannon

A cannon is a large military weapon that is supported on wheels or a fixed mount. Early cannons were made from smoothbore metal tubes loaded from the muzzle and worked manually. Allowing the wheels to go backward absorbed recoil.


A German monk named Berthold Schwartz is credited with inventing the cannon.

Small Arms

The first version of small arms were made as smaller models of beginning artillery weapons and were at first called hand cannons.

Patch and Ball

In the early period of small-arms creation, the powder, the patch or wad, the ball, and the primer were carried separately and were loaded into the gun separately. The powder was put into the barrel of the gun through the muzzle of it, followed by the wad; then the bullet was pushed in, and the flashpan was primed with a small amount of powder.

The Wheel Lock

Around 1515 an upgrade in the firing mechanism of small arms, called the wheel lock, was created. It was made up of a spring-driven wheel, which, when let go by a trigger machine, rotated a steel rim against a bump of iron pyrites, throwing a shower of sparks into the powder in the priming pan and firing the weapon. At around the same time as the wheel lock, gunsmiths created rifled barrels.

The Wheel lock was invented around 1515.






"Cannon," Microsoft Encarta 96 Encyclopedia. 1993-1995 Microsoft Corporation.


"Small Arms," Microsoft Encarta 96 Encyclopedia. 1993-1995 Microsoft Corporation.

Rich, John. "Backyard Ballistics." 1995-1997.


O'Connor, John J and Robinson, Edmund F. "Nicolo Fontana Tartaglia." December 1996


Parshall, Karen Hunger. "The Art Of Algebra From Al-Khwarizmi To Viète: A Study In The Natural Selection Of Ideas." 1988-1995


Parshall, Karen Hunger. "Biography of Niccolò Tartaglia."


Westfall, Richard S. "Tartaglia [Tartaleo, Tartaia], Niccolo." August 1995

Johnson, David Alan. "The Battle of Tewkesbury."