Simple Pressure PVC Blow Gun (113.6mph)

I made a simple, pressure blow gun that uses air pressure and can go at a much faster speed and with much more power than a human-powered blow gun can go. The purpose of this project is to greatly increase the speed and power of a human powered blow gun using only air pressure. The pressure blow gun can get up to a speed of approximantly 113.6mph (166.67 ft.per second) at approximately 80psi whereas a human-powered blow gun's speed is only approximantly 35.89mph (52.63 ft. per second). And the best part about it is that it is really fun to shoot because of its speed and power.

For this project you will need the following materials:

1. 3/4 in. pvc pipe
2. 3/4 in. pvc cap
3. 3/4 in. ball valve
4. pvc glue for any pressure
5. a hacksaw for cutting the pvc pipe
6. a measuring tape
7. a shrader (auto) valve (you can find them in most hardware stores)
8. a lid from a bottle that fits snugly into the pipe
9. sand paper
10. a drill bit that is the same size as the shrader (auto) valve (I used a 1/4 size drill bit)
11. a power drill
12. a hot glue gun
13. an air pump, it doesn't matter whether it is electric or manual
14. a permanet marker is also useful
15. paint(optional)
16. air pump
17. a stick that fits into the barrel snugly

The materials you will need for this step are the pvc pipe, the measuring tape, the hacksaw, sand paper, and a marker would also be useful.

1. First get the pvc pipe and measure out 18 inches of the pipe for the pressure chamber and mark it so you know where to cut it.
2. Then cut it with the hacksaw.
3. Next you will measure out 22 inches of the pipe for the barrel and mark it so you know where to cut it.
4. Then cut it with the hacksaw.
5. After you cut it you should sand the ends of the pvc pipe with the sand paper.

The materials you will need for this step are:

1. the pvc cap,
2. the power drill and drill bit,
3. the shrader (auto)
4. valve,
5. the pvc glue (I recommend using the glue outside for good ventilation), and
6. a marker would be useful.

Putting things together:

1. First you will get the lid and mark the approximate center of the pvc cap (I marked mine with an X).
2. Then you will drill a hole into the approximate center of the pvc cap.
3. After you have drilled the hole you get the glue and apply some to the rubber part of the shrader (auto) valve and also apply some glue in the pvc cap around the hole you drilled.
4. After you have applied the glue you will put the shrader(auto) valve into the hole and bolt it tight if it uses a bolt if not just pull it tight and let it dry for at least half an hour.

For this step you will need:

1. the shrader (auto) valve,
2. the pvc cap you put together in step 2,
3. the 18-inch pipe you cut in step 1,
4. the ball valve, and
5. the pvc glue (I recommend applying the pvc glue in an outside area for better ventilation).

How to put it together:

1. First you will get the pvc pipe and the shrader (auto) valve and the pvc cap you put together and glue it to the pvc pipe.
2. After you have glued that together you will get the ball valve and glue it to the other side of the pipe.
3. Then leave it to out dry overnight.

Notes: I did not glue the barrel onto the pressure chamber, that way I can load it, then twist it into ball valve that is on the pressure chamber.

To make this projectile you will need:

1. a stick that fits snugly inside the barrel (I used a broken broom stick),
2. the measuring tape,
3. the hacksaw,
4. the paint (optional), and
5. a marker would be helpful.

How to put it together:

1. First you measure out one inch on the stick and mark it for cutting.
2. Carefully using the saw, cut it at the mark.
3. After you have cut it, you can paint it if you want to (I recommend painting it outside, so you do not breath in the fumes). I painted my projectile red so it would be easier to see when I launched it. Now you have your projectile!

Here is another way to make a projectile, but it is more complicated to make. You will need a lid or something that fits snugly into the barrel (I used a lid off of a food coloring bottle because it fit really well), a hot glue gun, sand paper, and paint (optional).

1. The first thing to do is plug in the hot glue gun so it can start heating up.
2. Next cut the flap off the lid if your lid has a flap, then you will fill the lid with hot glue.
3. After the glue has cooled you should sand around the outside of the projectile so that it slides better inside the barrel.
4. Now you may paint it if you want to, (I recommend painting it outside so you do not breath in the fumes),

To pressurize and load your pressure blow gun you will need the pressure chamber you made in step 3, the barrel (which is the 22 inch long pvc pipe), the projectile you made in step 4, and the air pump (you can use an electric air pump or a manual air pump).

1. First you will make sure the ball valve is closed so no air leaks out when you pump it up.
2. Then pump it up to 80psi (I try not to pressurize it much higher than 80psi because I do not want to risk exploding the pressure chamber).
3. Next you will put the projectile into the side of the barrel that will be attached to the ball valve.
4. Then attach the barrel to the pressure chamber by twisting the barrel into the ball valve that is on the pressure chamber.

Now your pressure blow gun is loaded and pressurized!

To fire your pressure blow gun you will first need to know how to hold the pressure blow gun properly:

1. To hold it, you will hold the pressure chamber a few inches away from the ball valve with your right hand, and the end of the pressure chamber will be under your arm.
2. Then you will hold the ball valve switch in your left hand.

Now that you know how to hold it, it is time to fire it!

1. To fire it safely you will need to aim it at a safe target. (The target should be in a safe place with no person, animal or breakable items within range.) Safety glasses are recommended!
2. When the area is safe, take aim and turn the ball valve quickly so that the pressure is released at one time.

For safety, always fire away from people and buildings, I recommend using a cardboard box for the target.

Now I will explain how this pressure blow gun works.

The way it works is that potiental energy is stored in the pressure chamber in the form of air pressure, and when the potiential energy is released it forces the projectile out of the barrel at a high speed -- approximately 113.6mph (166.67ft. per second).

I tested the speed using two stakes that were pounded into the ground ten feet apart and then shooting the pressure blow gun so the projectile would pass the two stakes. I made a video recording of the process at 100 frames per second, then I used a computer to see how many frames it took to get between the ten foot mark. After I figured that out, I gave Google that information and asked how many mph it was going at, and Google gave me the amount. I also used the barrel as a human powered blow gun and I tested the speed the same way, and it only went 35.89mph (52.63 ft. per second). This shows that the pressurized potential energy greatly increases the speed of the projectile compared to the power of my lungs!