So we got an idea from the YouTuber Grant Thompson - "The King of Random" video on how to make a blowdart gun. We made a few variations. We thought that the bullet didn't go fast enough, so we added some pressure with simple, cheap, almost all at home parts, but can still pack over 5x harder than the average human could possibly make, if your not 30 feet underwater. If you like this 'ible, please take the time and click that little 'vote' button on the top right corner of the screen. It helps us out a lot!
FPS: Calculating soon
Average distance: About 87 feet with 20 PSI, results vary depending on PSI of bottle, length of barrel, and bullets.
Here's a video of it in action (Yes, this is slowed down a lot)
PLEASE check out Grant Thompson - "The King of Random"
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Step 1: Materials
- 1/2 in x 2 ft of PVC
- PVC Cement
- Coca Cola Bottle (Or any thick plastic bottle)
- Schrader valve
- Hot glue
- Duct tape (Optional, for decoration)
- 1/2 in PVC ball valve (We used a water valve)
- Pool noodle (Optional, for shoulder rest)
- Sticky notes
- Piece of paper, or party hat
- Adult supervision
- Hot glue gun
- Needle nosed pliers
- Bicycle pump
Step 2: Making the Barrel
The first step is making the barrel. You will need to get your 2 ft length of PVC and cut 9 1/2 inches from one end, and sand as necessary. Next, attach your ball valve to both lengths of PVC. Apply super glue to the longer length of PVC before you put on the valve.
Step 3: Making the Compression Chamber
Making the compresson chamber is the hardest part, it takes a little bit of patience. First, tip your bottle up side down. In the very center of it, with your hot glue gun on HIGH if it has the setting, melt the center of the bottom. The size will vary depending on the size of your schrader valve. You will want it really snug, so keep the hole smaller than the divit on the side of it. Once you have made your hole, insert your schrader valve in the bottle, and make the stem (long end) go into the hole. Use your needle nose pliers to pull it all the way through. We needed to use olive oil to greese it up and get all the way in. Make sure the schrader valve is secure by its divit.
Step 4: Making the Ammo
The ammo is pretty easy. First, make a paper cone, and hold it together with some tape of any kind, we used electrical tape because we are too lazy to get regular tape. or you can get a party hat, which we really do recommend, because its sturdier and you don't have to put it together, but the only ones we could find were $4.00 so we passed. Both methods work. Next, get a sticky note and hold it horizontal to the ground, as shown in the pictures, with a little bit of it sticking out to the left. Move that left part inward and down, then the right part inward and down, to create a cone shape. Next, use some tape (Again, we used electrical tape) to hold it together.
After you have the small sticky note cone done, we need to make it the correct size and cut it. To do this you will need to put the cone on one of your fingers, and push it in firmly into a piece of scrap PVC (Or an end of your barrel), but not so hard that it ruins the cone, and give it a slight twist. Pull it out, and you should see a curved crease. Use your scissors and cut that line.
Now you have that cut piece, we need a weight to balance it, and a nail to stick into trees and cardboard boxes. First what you want to do is put your nail in the hollow part of the cone, and press it down almost all the way, with about 2 cm of nail left in the hollow part. Fill the cone slowly with hot glue, about half way, maby a bit more. Pull the nail downwards a bit more, about 1 cm down, and making sure the nail is straight, let it dry. This can get hot, so you may want to use a cloth towel or napkin to hold it while it fully dries. This can take up to 3 minuets to fully dry. Now your ready to decorate and shoot.
Step 5: Assembling
To put together the compression chamber and the barrel you first will need to get the long length of PVC, and on the clear end, put a ring of super glue around the tip of the PVC, and insert that in the bottle, not going past the neck of it. We reinforced this with some electrical tape, and to help minimize leakage.
Step 6: Decorating
Now here's the optional part... DECORATING! We got a few inches of pool noodle and attached it to the super glued pvc length for a nice shoulder pad. We also covered ours with some duct tape to make it look cool. You can really do whatever you want to this.
Step 7: Firing
Now here's for the part we've all been waiting for... firing the device. A note before you shoot:
This can be dangerous, always use with adult supervision if not an adult already. Never shoot at ANYONE OR ANYTHING that could get hurt or damaged. You may want to wear eye protection, and don't shoot anything less than about 10 feet away. note that 10 is an estimate of the average distance of ricochet, and you may want to change the average depending on how much PSI you have in the bottle.
Now we have that read, lets get firing! First to fire, take off the 9 1/2 inch length of PVC and put a bullet on your fingertip of your other hand. Place the bullet point downwards through the PVC length and put back the PVC length into the ball valve. Next, put your device o the ground, and pump up the bottle through the valve attached to the bottom of the bottle. We recommend 10-20 PSI. You can do more, but that can get pretty dangerous, so don't have it near your face, do more next to your hip. Now, place the long length of PVC on your right shoulder if your are right handed, left shoulder if you are left handed, with the bottle behind you. Place your dominant hand on the valve, and your other hand farther along the barrel for more stability/support. Once you have selected your target, something like a tree or an empty cardboard box, and making you are AT LEAST 10 feet away from your target, quickly open up the valve, and if all goes well, you have successfully shot your blowdart gun! If you only hear hissing of air coming out, you either have a faulty connection at the small length of PVC, you didn't turn the valve fast enough, or your bullet is made wrong. Try trimming the edge of your bullet and trying again.
Step 8: Doing More
Now you have this blowdart gun 'base' try adding/changing some stuff to it. We have found that using a 2L bottle increases results dramatically, along with changing the barrel size to around 2 feet. Also try making new bullet designs, cone skinnier and longer, less/more hot glue, or multiple nails.