If you love Nerf guns, but would rather the guns were made of more sustainable material, then this DIY project might be right up your street. Using little more than recycled electrical components, cardboard, and paper, you too can make this working DIY cardboard rifle.
Follow this long (but relatively simple) guide to finding out how.

As you can imagine, like any project of this nature, you'll need some tools and materials before you get started.
Materials and gear needed
- 9/32ths of an inch (7mm) thick cardboard (old boxes or other)
- Brown paper
- Old DC motor x 2
- Battery
- Battery connector
- Old plastic syringe (the plunger) x 2
- Rubber bands
- Wooden skewers to make dowels
- Hairpin
- PDF plans for the gun parts
- Modeling knife
- Superglue
- Soldering kit
- Electrical wires, resistors, and soldering gear
- Hot glue gun
Optional
- Paper cups for targets
With all your tools and materials in hand, it is now time to get on with this epic, but awesome, build.
Step 1: Cut out the parts needed
The first step is to download the plans for the gun and print them out to scale. We have included a link to them in the materials list above.
Please note, the templates should be printed on A4 paper.
Once you have printed out all the templates, cut them out, and transfer them to your cardboard. Pin the plans to the cardboard and cut them out.
With that complete, draw around the outline of each part using a ballpoint or marker pen.

Once you've transferred the plans to the cardboard, carefully cut out each piece using a sharp knife. Ensure you cut as accurately and precisely as possible. Consider using a metal ruler as a guide to help you here.

Step 2: Assemble the main gun
With all the parts printed and cut out, we can now begin the main assembly. Take the main grip and barrel piece and affix the central part to the gun barrel. You can find these on the first five pages of the PDF template.
Please note there appears to be a disparity between the plans provided and the video, but the overall shapes of the pieces are pretty much the same.

Glue the parts together using some superglue or PVA glue and leave it to fully cure.

Add the two other strips to the same central piece to build up the gun as shown below.

Next, cut out your paper into a long strip 18 and 7/64ths of an inch (46cm) wide. You can find this part on the "Barrel Layer 1" of the PDF template.
Take a long cylindrical object, like a rod, and roll the paper into a loose cylinder to make the main gun barrel. It will need to be 5.8ths of an inch (1.6cm) in diameter once complete.

Glue the paper together to form a solid, yet hollow, cylinder. Next, take your modeling knife, and bevel one end of the barrel.

Take the barrel and add it to your main gun assembly. Glue it into place as needed using a hot glue gun.

With that complete, take your old syringe, and remove the main plastic plunger. Next, remove the main rubber cap from the plunger, and glue it to the axle of a DC motor.

Rinse and repeat for a second identical motor. Glue the motors together in parallel. These syringe plunger heads will be turned by the motors to propel the projectiles.
Glue the firing motors into position on the main gun assembly as shown below.

Step 3: Continue building up the body of the gun
With that complete, take the next pieces of the grip end of the gun and glue it into place on the main assembly.
Also, insert two short dowels using your skewers or toothpicks, and the other parts shown below into place. They should be as long as the full width of the gun.

With that complete, take the main trigger parts of the gun. Assemble and glue them together as needed. You can find the templates on the "Body Layer 5" page of the template document.

Leave to dry, and then bore two holes through the cardboard trigger as shown below.

Insert the trigger onto the rearmost peg of the main assembly as shown.

With that complete, make another narrow wooden dowel and glue a wooden ring to one end. Insert it into the handle end of the gun and connect the cardboard trigger to the pin using a short rubber band or doubled-up longer band.

Test the trigger action. It should move freely when you move it with your finger and then return into place once you release it.
Next, take the magazine lock spring arm, and a spring, and add them to the other wooden dowel on the gun assembly.

With that complete, take the covering plate for the gun spring and trigger and glue it into position as shown below.

Step 4: Complete the electrical firing mechanism
With that complete, wire up and solder the DC motors in sequence. Add two longer lengths of wire to form the battery connection wiring.

With that complete, add the other half of the gun and glue it into place as shown below. Then add a line of hot glue to one edge of the gun behind the motors, and glue the wires into place

With that complete, solder the wires to your small push button, as shown below. Complete the circuit by soldering the wiring to a battery connector too.

Next, cut a rectangle of paper 4 and 9/64 inches (10.5cm) wide, and roll it into a thin, hollow cylinder, around another skewer. Glue the end piece to the main cylinder to hold the paper together.
Flatten one end of the cylinder using a pair of pliers.

Soak it in superglue and leave to solidify. Then bore a hole through the center of the flattened end of the cylinder.
With that complete, add a short length of wood dowel and taper the other end of the cylinder.

Next, cut a strip of paper 19/32ths of an inch (5cm) wide, and roll it around the main cylinder body, as shown below.

With that complete, we can begin to complete the main firing mechanism of the gun. First, take the needle-like rod, and insert it using another wooden dowel to the top of the gun trigger.
Fix it into place using two cardboard rings.

Add the thick cylinder to the free end of the rod, and glue it into place to the main body of the gun. The rod should be able to move freely through the thicker cylinder when you depress and release the trigger.

Step 5: Finish off the barrel
Connect the electrical components to a battery, and test the firing mechanism. You can wait to do this once the magazine is built (see step 8).
When you depress the trigger, the rod should move forward to engage one of the bullets with the syringe tops on the motors.
The motors should engage the bullet and accelerate it down the barrel.

Next, take another strip of 4 and 21/64ths of an inch (11cm) wide paper, and roll it into another cylinder around one of your wooden skewers. This will form the dummy cleaning rod part of the end of the gun.
Then make another larger bore cylinder with the same inner diameter as the total width of the first cylinder. This will form the barrel muzzle piece.
Then make two equally sized rings of the same width and thickness of the thicker cylinder. These parts will be used to complete the "business end" of the main barrel.
You will also need to make a loose ring of paper to thread between the main barrel and the dummy cleaning rod. squeeze the middle of it once in place, and glue together to make a figure-of-eight connecting piece.
Thread them over the end of the main gun barrel and glue them into place, as shown below. These won't serve any real purpose, except for decoration.

Step 6: Add the main bodywork to the gun
With the main firing mechanism, magazine, and barrel now finished, the piece is basically complete. However, it doesn't really look like a "proper" gun.
Now, we'll turn out attention to adding some finer details to the cardboard gun.
Let's first build up the main gun body. Take some cardboard and cut a strip 2 and 23/64 inches (6cm) by 11 and 13/16 inches (30cm). Strip off one facepiece of the cardboard to expose the ribbing underneath.
You can find the templates for these pieces on the "Accessories Layer 3" page of the template document.

With that complete, bend it into an L-shape along its longest middle, and attach it to one side of the top of the main gun body. Glue it into place as needed.
Next, cut another strip of cardboard to the dimensions needed to build a handguard for the main gun. Bend it into a C-shape and then attach it to the underside of the main gun body.

Glue it into place, as needed.
With that, cut out the part to make the "Accessory Layer 2" from the template document. Bend it into shape, as needed, and glue it to the underside of the handgrip you just attached to the cardboard gun.

With that complete, cut some small strips of cardboard and remove one face of the board to expose the ribbing once again. Glue these into place to make some rails to the sides, top, and bottom of the gun body.

Next, trace out and cut out "Accessory Layer 1" pieces. Take the first piece and glue it into place to form an extended rim to the side of the exposed firing mechanism section of the cardboard gun.

Rinse and repeat to make a second piece, and attach it to the opposing side of the gun. Next, take the bottommost "Accessory Layer 1" piece, fit it between the two pieces you just affixed into place to close off the exposed firing mechanism portion of the gun.

Next, trace and cut out two of the last piece on the "Accessory Layer 1" sheet. Glue them into place on either side of the rear section of the gun above the grip and trigger.

Step 6: Make the telescopic stock
With that complete, cut another strip of paper 9 and 1/16th inches (23cm) wide. As before, roll it into a hollow cylinder around a cylindrical object. This will form the main rod for the telescopic stock.
Rinse and repeat to make a second identical piece.

With that complete, cut another strip of 1 and 37/64 inches (4cm) wide paper, and roll it around the one end of the other cylinder you just finished. Do the same as the other stock arm.

Seal both the pieces together using superglue. Next, cut another strip of paper 5cm wide, and roll it around the same cylinder except at the other end.

Do not glue these ones to the main stock arms, however. These will be used to act as guide rails for the stock arms on the main body of the gun.
With that complete, mark out series of equally spaced notches along each of the stock arms. These points will make the main telescopic adjustable locks for the stock.

Carve out notches at the points marked. With that complete, take a hairpin, split it into two, and hook the ends. These will be used of the telescopic arm locking springs.

Glue each to one side of the arm guide rail rings you created earlier. Make sure the folder part of the pin is facing upwards towards the center of the ring -- so that it can engage with the notches on the arms.

With that complete, insert the notches arms into the rings, and ensure that the notches can engage with the springs.

With that complete, we can now continue to build the stock. Mark out and cut out the parts needed from the "Butt layer" of the template provided. Assemble the pieces as needed to fully build the cardboard gun's butt. as shown below.

With that complete, wrap a strip of darker brown paper around one end of the butt, as shown below.

With that complete, glue the fixed butt arm cylinders to either side of the butt. Then glue the butt arms guide rings to the main body of the gun, as shown below.
Test the telescopic action, and adjust if needed.

With that complete, take the capping piece of the butt from the "Butt Layer" of the template, and glue it into place on top of the butt.

Step 7: Continue adding more details to the main gun
With the main butt now more or less complete, we can move back to the main gun. Add another small rail from the rear gun sight to the back of the gun.

With that complete. cut out a c-shaped capping piece for the final exposed part of the rear of the gun. Glue it into place. The hole left in the top of the gun is on purpose -- this is where the battery will be held once the gun is complete.

With that complete, cut out prepare the guard piece for the trigger of the gun. Glue it into place as needed.

With that complete, we can now move on to making the scope for the gun. Cut out a strip of paper 8 and 21/32 inches (22cm) wide. Roll it into a large cylinder until it is 25/32ths of an inch (2cm) in diameter.
This will form the main body of the scope.
With that complete, cut some more strips of paper 19/32ths of an inch (1.5cm) x 2, 1, and 3/16 inches (3cm), 25/32ths of an inch (2cm), 3 and 23/64 inches (6cm) and 25/64ths of an inch (1cm) in width.

Roll them into wide bore cylinders with their inner diameters big enough to be threaded around the main scope cylinder.

Glue them into place on the main scope piece, as needed.

With that complete, make two dials, and glue them into position on the main scope as shown below.

Next, make the two scope support struts and glue the entire assembly to the top of the main gun.

Step 8: Complete the magazine
With the scope now completed, we can make the gun's magazine. Cut out a rectangle of cardboard with a slit in the middle. Make a second identical piece as well.
The templates for these pieces can be found on the "Magazine Layer" of the PDF template.
Then cut the narrow c-shaped piece of cardboard and glue it around the three sides of the slotted piece.

Glue the pieces together, as needed. With that complete, grab your metal wire, and bend it into a right-angled spring.

With that complete, Cut the ammo plunger piece from the "Magazine Layer" of the template provided and glue it to one end of the spring you just completed.

With that complete, glue the other end of the spring to the base of the main magazine ammunition container.

With that complete, enclose the magazine spring and plunger with the second piece of slitted cardboard. Glue and another small piece of cardboard to the top end of the magazine to leave enough room to load the bullets later on.

Now we need to fill the magazine with some actual bullets. We will make these from paper.
Cut a series of 1 and 3/8 inches (3.5cm) wide strips of paper, and roll them into a series of cylinders. Tapper the front end of each to make a cone, and then color them in red (or whichever color you'd prefer).

With the bullets complete, load them into the magazine until the spring of the magazine prevents you from loading any additional bullets.

Step 9: Add the finishing touches to the cardboard gun
With the magazine completed, we can now complete the rest of the piece. Cut a series of rectangular holes in the gun's handguard to make mock ventilation slots.
Then make a series of cardboard circles and glue them to the main handguard of the gun. Add some others to the main body of the gun.

With that complete, insert the magazine into its loading slot on the gun. Push into place until the locking pin triggers and holds it firmly inside the gun.
With that complete, connect the electrical circuits to the battery, and insert the battery into its repository on the top of the gun (the void in the rear c-shaped caping piece we added earlier).

Tuck all the cables inside the body of the gun.
With that, your DIY cardboard gun is now complete. Now, all you need to do is set up some targets, and give the gun a test drive. Paper cups are a great option, but you can use whatever you have to hand.
If you enjoyed this DIY project, you might enjoy this modified Nerf gun that can fire foam balls at 70 mph (11.7 km/h)?