Truly Semi Automatic Knex Gun




Introduction: Truly Semi Automatic Knex Gun

This gun is based off of KNEmovies design, but not his mechansim. the mechansim may be similar to his, but mine is not that complicated. My gun is not that powerful, as it only shoots 5-10 ft. I hope you enjoy my semi - auto gun.

Step 1: The Handle

This is the construction of the handle. Very simple.

1 Build 2 of these (a)
2. Build 3 of these (b)
3. Connect one of (a) to a blue rod.
4. Connect all of (b) to the blue rod.
5. Connect the last (a) to blue rod
6. Top view of the handle
7. Side view of the handle

Step 2: The Pusher

This is the pusher that pushes the bottom part of the firing part that makes the trigger come back to its original position.

1. A view of the pusher.
2. Make this. (a)
3. Side view of (a).
4. Add 4 red connectors to a blue rod.
5. Add a blue rod to the red connectors, then you add an orange connector and the orange track
connector to the rod. (b)
6. Connect (b) to (a).

Step 3: The Magazine

This is the magazine that shoots white rods. Not that far though... 5 - 10 ft.

1. The magazine.
2. Front view of magazine.
3. Build 2 of these. (a)
4. Build these. (b)
5. Build this. (c)
6. Side view of (c).
7. IMPORTANT! Must have these 2 spacers on (c) or else the trigger will be EXTREMELY difficult to be
pulled back by rubber bands! ( If you don't have these, you'll realize what I'm talking about ).
8. Add 1 (a) to (c).
9. Add the last (a) to (c).
10. Add 1 (b) to (c) and the other (b) to (c) as well. Then add yellow rod on top.

Step 4: Some Pieces You'll Need

These are just the pieces you'll need later.

1. Build one.
2. Build one. (The middle tan connector is really a blue metallic connector, so add that instead)

Step 5: The Trigger

This is the trigger. Really simple.

1. Build 3 of these. (a)
2. Connect all of (a) to a blue rod. Look carefully where the rod is connected.

Step 6: The Firing Pin

This is the firing pin that once you pull the trigger, the firing pin will pull back itself and shoot.

1. Make these. (a)
2. Connect (a) just like this.
3. Make this. (b. The black rod is a gray rod, so don't be freakin' out about not having this...)
4. Connect (b) to (a).

Step 7: The Top Part

This is just the part that covers the mechanism. It's not needed, but go ahead and build it anyways...

1. Build This (a)
2. Remember the 3 y connectors.
3. Build 2 of these. (b)
4. Connect the (b)'s to (a).

Step 8: The Frame

This is the frame that supports everything.

1. Build 2 of these.
2. If you cant see far, i added this (a)
3. Same with 2. (b)
4. connect (b) to (a)

Step 9: Orange Connectors

In this step you will add orange connectors to the second frame you built earlier.

1. Add orange connectors to where shown.
2. If you cant see far, then look at this picture.
3. " "

Step 10: Adding Firing Pin and Trigger

In this step you'll add the firing pin and the trigger. It shouldn't be complicated to place them on the frame.

1. Place the firing pin and trigger where shown.
2. If you can't see far, see this. Place firing pin here with a blue rod.
3. Place this after you put the black/gray rod in the orange connectors.
4. Place trigger here
5. This is how it should be

Step 11: Connecting Frames

Connect the frames.

1. Take your both frames.
2. Connect 1 of the frames to all the orange connectors and the blue rods.

Step 12: Connecting Parts

In this step you will connect the pusher and the other parts you built earlier.

1. Take you pusher
2. Connect it to where shown
3. This is how it should look like
4. Take the blue rod with the 2 tan clips and the blue metallic one
5. Connect it to where shown.
6. Take your blue rod with the 5 green connecters
7. Connect to where shown

Step 13: Connecting Magazine, the Top Part, and the Handle

In this step you will connect the magazine, the top part and the handle.

1. Take the magazine
2. Connect it
3. Very important to have 1 blue spacer in each yellow rod!
4. Take the top part
5. Connect it
6. This is how you connect
7. Take your handle
8. Connect it here

Step 14: Rubber Bands

In this step, you will add rubber bands to the finished gun. You will need plenty of rubber bands for this step.

1. Take your rubber bands
2. Place rubber band on the firing pin. Stretch and put it around the 2 white rods with the orange connector to the other side of the firing pin.
3. Place only 1 rubber band from the white rod connected to the 3 purple connectors down to the blue rod as shown.
4. Add only 2 rubber bands from the pusher to the blue rods. (1 blue rod is on one side, the other on the other). Add more rubber bands if the pusher isnt pushing the firing pin so the trigger can come back and and shoot correctly.
5. (Second blue rod is shown)
6. Add plenty amounts of rubber bands from the green connector's blue rod to over the next blue rod and to the trigger. :)
7. (Where to place the rubber bands in the blue rod)
8. You are officially weilding a truly semi automatic gun created by ednator55. Enjoy and don't "kill" noone!

1 Person Made This Project!


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9ydens Knex
9ydens Knex

1 year ago

lets go i found the instructable! Now i need to upgrade the range...


1 year ago on Step 14

For me it truly is semi auto but the range is terrible. The range for me was 1-2 feet only.


Reply 13 years ago on Introduction

georgie porgie pudding pie, kissed the girls and made them cry sorry, I had to


Reply 11 years ago on Introduction

georgie porgie pudding pie, kissed the girls and made them cry sorry, I had to too


Reply 11 years ago on Introduction

both of you are wrong, its georgie porgie pudding and pie, kissed the girls and made them cry.

ps...have you ever kissed a girl?....... 


Reply 13 years ago on Introduction

it really annoyed the kid everybody did it too lol


7 years ago

Add a thick rubber band, I got 15 ft by doing it


7 years ago on Introduction

i wish i can make this but i dont have enough pieces try to make one with less pieces


9 years ago on Introduction

that is an awesome gun i might make it but put the mag the other way round so it looks like a proper gun and have something to push the bullets up ... :P

Element Force
Element Force

10 years ago on Step 2

I have no orange connector like that can i use something else


10 years ago on Introduction

if you don't build the orange conector and the bleu rod it shoots better nice gun anyway i like the mech