Do you want a highly efficient round that can maximize the power of your potato cannon, so that you can reach distances that with a normal potato you can only dream about? This Instructable will teach you how to make the bullets that can make those long shots.
Note: These are designed for use in barrels with 3 Centimeter diameters and wider, for smaller barrels try my other instructables:
Step 1: Materials and Tools
A drill with a 2 Millimeter drill bit.
A pair of pliers.
A pair of scissors.
A compass, the type used for drawing circles.
A metal funnel or a large marble.
A small pan.
A safety clip.
A washer, It should be between 1.5 Centimeters and 2 Centimeters wide. The center hole needs to be about 5 Millimeters wide.
A piece of wire about 11 Centimeters long.
A sheet of plastic at least a Millimeter thick, you can get it from display books the type with the clear pockets. (If you can't get this you can just use the plastic lid from an icecream container, although it is not nearly as strong).
Two fishing sinkers about the size of marbles.
Template A (Print the picture of the circle and cut it out).
A screw about 3 Centimeters long.
A rubber bung for the nose "cone", from the bottom of old computers or appliances, You may need to improvise or do some dumpster diving to get these. Alternatively get someone to distract your tech teacher while you have a go at the computer.
A piece of pressure or construction pvc, although you don't want the bendy type. It should be about 15 Centimeters long.
A Bolt about 3 Centimeters long 4 Millimeters wide and a matching nut.
Step 2: Preparing the Pvc
For preparing your piece of pvc you're will need to use a technique called Flaring. I thought I wouldn't reinvent the wheel, since there is already a great how-to on this
(here is the link):http://www.burntlatke.com/rocket.html
(Me) Done yet?
(Me) How about now?
(You) Quiet, I'm concentrating.
"More time passes"
(You) Great, finished flaring now all I have to do is put the end cap on.
(Me) NOOOoooo, You only need to do the flaring and then go on to Step 3.
Note: All credits to the author of Burnt Latke. While there check out his other stuff.
Step 3: The Bullet Starts to Take Shape.
First plug your glue gun in.
Okay so now that your pvc is flared, you need to wipe it thoroughly with some paper towel. This is important because the hot glue won't stick nicely to oily pvc. Now take some fresh paper towel and shove it halfway into the pipe like in picture 2, this is so you don't use so much glue. Next holding the pipe with the flared end at the bottom, cover the top of the paper towel with hot glue and quickly put one of the sinkers on top of the glue. Cover this with glue then place your second sinker on the glue. Using your drill make a hole in the sinker all the way through, this is where your going to screw your nose cone on. Now screw the nose cone on slightly, fill the space between the sinker and the top of the pipe (If it overflows a little that's fine, you can just wipe it off). Now quickly screw the nose cone all the way in and wipe of any excess glue. Okay so now once the glue has dried take the bolt and glue it in just like in picture 2, it should stick out of the pvc about 2 Millimeters.
Step 4: The Tail
Okay now remember how you printed out Template A ( A.K.A That picture of the circle thingy)? Now we are going to need it so if you didn't go print it out you can do that now, Don't worry I'm not going anywhere. Once you have printed it, cut it out. Now cut a circle out of the sheet of plasticabout 3 Millimeters bigger then the template. Use the compass, so you get a good circle, you'll see why in a minute. Now take your template and put it on top of your cut out circle and make a little mark on the edge of the plastic circle by each of the solid lines on the template. With a ruler connect the marks just like in picture 3. Then use a compass to make a circle with a radius of 1 Centimeter (The radius is the distance from the center of the circle to the edge of the circle). When you are done your circle should look like picture 3. Next cut along the line you drew but don't cut all the way to the middle stop at the little circle you drew earlier. Now using the edge of a desk or door, bend the tail like in pictures 4-6. now drill a hole in the center of you tail like in picture 6, it will need to fit over the bolt on your bullet.
Step 5: Attaching the Tail.
First you're going to have to bend your piece of wire like in the photos. After that take the tail and slide it on top of the bolt on your bullet, then slide your shaped piece of wire on. Then put the washer on top of that and finally screw the bolt on top of that. Have a look at picure 7 if the instructions where not clear enough.
Step 6: The Tail Ribbon.
The tail ribbon is just a piece of ribbon about half a meter long. It is attached using a safety pin. The tail ribbon is not neccesary but it does make it easier to find.
Do & Don'ts
Do have fun with this.
Don't be stupid with this.
Do shoot this in a clear area i.e not somewhere with people to hit.
Don't shoot this where it will land on concrete or any very hard surface, the pvc will shatter.
Hope you found this instructable easy to understand if you didn't just tell me and I can help you out.