Compact Chaos - a Compact K'Nex Sniper




Posted in PlayKnex

Introduction: Compact Chaos - a Compact K'Nex Sniper

Welcome to the Instructable for Compact Chaos, a compact sniper rifle and my first K'Nex gun that actually worked. With a few #64 rubber bands, I was able to reach a range of about 30 metres and easily pierce an empty drinks can. I apologise for how the image quality isn't the best, but considering they were somewhat rushed and taken with an iPad Mini, they actually turned out quite well.


-Good range


-Low piece count


-Can shoot pretty much anything you can put in the barrel - 3mm dowels work the best, since they can be sharpened for some serious damage.

-Never jams


-Somewhat flimsy

-Barrel is an absolute b**** to build

-Looks a little strange

Step 1: Parts List

Here is a list of pieces required the the gun. Included is the parts for 3 shots. Any pieces with irregular names (Blue connector with slot, Ball joint socket, Black-blue hinge Etc.) will be shown in pictures for your convenience.


Green: 106

White: 65

Blue: 17

Red: 5

Grey: 4

Black: 2


Dark grey: 23

Light grey: 3

Orange: 13

Red: 23

Green: 14

Yellow: 62

White: 23

Blue with slot: 3


Black Y-clip: 46

Blue spacer: 10

Grey spacer: 1

Yellow connector with tab: 1

Black-blue hinge: 2

Tan clip: 6

Blue clip: 7

Ball joint socket: 2

Step 2: Scope

This is the sight that is mounted atop the gun.

Picture 1) Build both of these.

Picture 2) Build all 5 of these.

3) Built this. Note the Y-connectors that are rotated 90°.

4) Find 7 blue rods.

5) Attach 3 of the blue rods like this

6) Slot 2 of the pieces in picture 2, as well as the piece in step 3 onto the blue rods.

7) Add the other side of the sight.

8) Use the 4 remaining rods to fasten down the roof.

9) Also, build this. We'll use it later.

Congratulations, the scope is complete!

Step 3: Bipod

This is the support for the barrel, when resting the gun on the ground.

1) Build this.

2) Build both of these.

3) Build this. The tan and blue clips can be reversed, or swapped out entirely.

4) Connect the legs to the slider we just built.

5) Get 2 white rods.

6) Add the slider to the red rod, then use the white rods to attach the legs to the white connector.

Congratulations, you've finished the bipod!

Step 4: Handle and Trigger

This is the handle, and the mechanism to hold the pin back until it's released.

1) Build this, and get a green rod. It helps to wrap some tape around the rod, but it isn't necessary.

2) Built this.

3) Connect them together like this, using the taped rod.

Now for the handle:

4) Build this.

5) Build this.

6) Build both of these. Don't forget the white rod.

7) Add the doohickey from picture 4 onto the white rod.

8) Add the other half of the handle.

9) This could be difficult. Put the green connector onto both blue rods, on each side. Be careful doing this, it's easy to break the green connectors.

10) Connect the blue connectors to the bottom of the handle.

11) [Optional] If you want, you can add wheels to the white rod; it makes the handle considerably more pleasant to hold.

We're done here! Now it's time to build the stock.

Step 5: Stock

This is the part of the gun that houses the pin guide, and allows you to steady the gun.

1) Build the pin and pin guide. Black rods are highly recommended, as is electrical tape, but not necessary.

Now for the stock and rear body:

2) Build this.

3) Build both of these. Note the missing white rods.

4) Find these 4 things

5) Attack the 2 halves together, using the white rods, The tan clip goes in the corner. Keep the grey connector for later.

6) Slide the object from picture 2 into the square, and secure it through the white connector with a green rod. This one doesn't have to be taped, but it can be.

7) Build both of these. Don't forget the blue rods.

8) Slide the big block onto the 3 blue rods. Now we can add the grey connector, between the red connectors in the corner.

9) Add a blue clip to the blue rod at the back, in the middle.

It's complete! Be warned - next step is going to hurt. Lots.

Step 6: Barrel

This is where the trigger will be held, as well as the ammo. I really couldn't bring myself to take this apart and rebuild it (Sorry!), but it has a relatively simple design so it shouldn't be too difficult to build. The rows of Y-connectors are to make it easier to snap the rod into the row of yellow connectors, but they also conveniently reduce friction in the barrel, which is an added pro. Picture 4 may be a little unclear; it's a ball joint socket placed on it's side and held in place with the tan and blue clips. If you want, the lower row of connectors can be joined to the upper row with green rods, but it isn't necessary, I'm just lazy.


Step 7: Assembly

The most fun step of all!

1) Attach the handle to the stock. It should clip in pretty easily.

2) Close-up of 1.

3) Add your rubber bands here. Loop them around the grey rod for now.

4) Now that we've got the rubber bands on, we can clip this little thing above the barrel. The easiest way is to remove 4 of the Y-clips, attach them to the red connectors then clip it all back onto the grey rod.

5) Clip the pin guide into the bottom of the yellow connector, and slide the tip of the pin into the barrel.

6) Now we can add the Stock onto the barrel. Due to how we added the green connector to the handle as we built it, it should be much easier to clip in. Once this is done, don't forget to attach the pin guide to the little grey connector in the stock, otherwise it won't keep the pin steady.

7) The trigger can now be added - be sure not to twist the grey connector that will block the pin. Once it's in, add a small rubber band around it.

8) Clip the scope onto the rail-thing we added in picture 4.

9) Open up the bipod and attach it to the grey rod running through the middle of the lower row of connectors in the barrel.

10) Finally, loop your rubber bands around the firing pin. You don't have to use a decapitated grey connector, but I had one lying around and I don't have many ball joint sockets.

Step 8: It's Complete!

This is my first real Instructable, so feedback is much appreciated. Thanks for building!



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    I'm in the middle of making a knex gun instructions line called Tiny Terrors,

    It is only block triggers and no triggers(less often no trigger), so if you hate block triggers, then don't touch this line.

    Dude can u make a video for this because I can't understand the last part on how to load it

    This thing... Is frikkin' cool. I had to improvise on some of the pieces used for spacing, but that's it. I love how smooth it cocks and decocks. I modified an old broken yellow connector for the trigger, and use a single rubber band for the firing pin and the trigger tension, which the black y-connectors let me dial up or down. It's one of those big red ones from newspaper bundles. They are awesome to use for many things. I had disregarded the sight as unnecessary originally, to save pieces, but I think I'm going to go ahead and build it. That, or make custom pin sights. Thank you for this design.

    3 replies

    I found two big, but easy to fix isses. The priming handle, the grey connecter, would sometimes pop off while cocking. Not good. Caused it to dryfire and send my ram-rod out the end of the barrel. Lost the socket. I fixed this by taking an orange connector, and clipping it onto the bottom, guide rod, and slipped the ram-rod through the center hole of the orange connector. This fixed that. I also took and put a grey connector on top of it to make a rear sight, and clipped an orange clip with a tab onto the black y-clip that kinda looks like a sight. This makes a great set of sights. Wrap tape around the joint of the orange and grey connectors, and slide the orange connector back up to the front of the rod to keep the friction down. without the tape, your grey connector will pop off from the impact.

    The second was that, on firing, the back end of the guide rod would come unclipped. I fixed this by taking two orange connectors on a white rod and slipping them down on either side of the clip for the guide rod. I put a green connector on the same white rod, then a white rod to a yellow, then a white rod to a 2-way grey, and made a sort of rail on top of the stock toward the back, that clipped in place on two white rods slipped through the holes just above the blue rods that hold the stock in place.

    Just turned the bipod into a tripod and made it to where it can be folded up to the bottom of the gun and clipped in place using a ball joint.

    @nerfrocketeer Thanks man, it means a lot :D. By the way, the design for this is entirely my own. I've been experimenting with different mechanisms in the barrel, and came across the use of the ball socket by myself.

    4 replies

    Hey man!

    I know you're new to this site, but when responding please use the reply button. It makes your comment show up in the other persons discussions tab, which means they can get back to you after they read your comment! Again glad to have you on this site and I hope to see more of your projects!

    Thanks - The only reason I didn't use the reply feature was because I was using the iPhone app at the time.

    Oh, okay that's fine! I know my android app has a reply button. I know if you use the internet instead, it will also let you use the reply button. It's all fine though. =D

    Hmmm... Well great first instructible! I'm interested to see what else you'll be making!

    Hmm, it happens here too eh? Well, I think it's epic. Good job and congrats on the feature! Don't listen to them...vv

    I have to agree with you on this. While I appreciate the effort he took to build it, the fact that he took the NAR barrel design and most of the TR's stock without giving any hint whatsoever of credit to the people who designed it infuriates me, although he did modify the barrel slightly

    Nonetheless, congratulations on the feature.