Knex Gun

i made a modification to killerk's knex gun. so this basically looks different and i've noticed a few changes. look here to see and build. this is my first instructable please comment on how i did

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Step 1: Start

Items list
*2 red
*1 black
*3 gray
*1 yellow
*18 green
*23 white
*2 orange
*4 brown (the small connectors with one connecting side and a pole sticking out of the side)
*4 K'nex men hands
*3 K'nex men arm socket joints
*3 dark gray
*2 black hinge pieces
*12 blue washers
Masking or duck tape (using duck tape might leave residue on your piece if taken off)
rubber bands (you will figure how many you want after i finish this instructable)

ok go gather these pieces and get back to the computer at once!

Step 2: Strart Building the Barrel

Ok now that you have the pieces, you can take 3 white connectors and attach them to one gray rod like so

Step 3: Build the Ram Rod

Now start the ram rod. take a brown connector and attach it to the black rod. it is also recommended that you sharpen the end opposite to the direction of the pointing end on the brown connector. notice that it is a blunt end. DO NOT sharpen it all the way! this could cause a freak accident in which could injure someone.

then insert it into the rest of the barrel as see in the picture

Step 4: Rest of the Barrel

now add another gray rod onto the white connectors like in the first picture.

then add more white connectors like in the second picture. along with a socket joint

then add another socket joint on the same rod with the same direction. also add 3 blue washers onto the upper rod.

Step 5: Trigger System

Now we shall add the trigger system. take the 2 black parts of the hinges and attach them to the lower gray rod as in the first picture

then take one of the hands from the K'nex men and attach it to an orange connector. slip it on to the top gray rod and then add another blue washer after

Step 6: Complete the Barrel

now add 14 more white connectors to the 2 gray rods. i used some black ones, but they are the same. they come in another set.

then add a brown connector onto the top rod and point the top of the connector towards the center of the white connectors

after that just add 2 more white connectors. you can also put a pointer at the front of the gun with a green rod attached to the top. this is optional

Step 7: Another Gray Rod

now you must add a gray rod to the other side of the barrel. you have to add 6 blue washers to the part where the trigger is. i used gray washers. these also come in another set. they are the equivalent to 3 blue washers. (1 gray=3 blue). also add a socket joint to the front of the gun, clamp side attached to the gray rod we just added.

Step 8: Construct the Handle

ok now we are ready to construct the handle. take 2 red rods and 18 green connectors and assemble them like in the picture. when you build the handle, make sure that you attach one rod to the end of the green connector, and the other red rod goes on to the 2nd last clamp of the green connector. this is hard to explain. if you get the picture then good for you, if you don't then see the 2nd picture and you will. and ones again i used pieces from another set same effects, different color.

Step 9: Attach the Handle

now you must force the gun handle into the gun. attach the handle into the area between the 2 socket joints. just push it. there is no magic way to get it in there. make sure that when the gun is being pointed in your face that the flat side of the handle is on the right side. this is only for hand comfort reasons. you can also apply tape around the handle (optional).

the gun should now look like this (ignore the colors)

Step 10: The Ram

Now get 3 dark gray connectors and attach them to the hands for the K'nex men.

then attach those pieces to the back of the ram rod pointing upwards.

after take 1 brown connector and attach it to the ram making the pole sticking in opposite direction to the barrel. then take an orange connector and attach it to the end of the ram like in the 3rd picture

then take a yellow rod and brown connector and attach it to the orange connector just as it is in the 4th picture

Step 11: The Rubber Bands

apply the rubber bands to the ram from the sides of the front of the gun all the way to the back of the ram. when you apply it to the back of the ram, make it like a cross in the picture

Step 12: Trigger Rubber Bands

Now we must attach rubber bands to the trigger for an auto locking feature. take the band and push half of it through the gap next to the 2 gray washers and connect it to the black tip of the trigger. the other end goes onto the bottom of the handle and hangs on to the rod of the handle sticking out of the end.

Step 13: Finished Ram

See the finished ram

Step 14: Voila!!!

ok this is the finished product. the amount of rubber bands you put it up to you. don't blame me if you get snapped in the fingers or anywhere else. and i take no responsibility for any pain you cause to others. this is a powerful gun. it can shoot up to 200ft which is pretty far. i dunno about the fps. just guess hah. i give my thanks to killerk for inspiration and ideas, the old guy who make K'NEX for actually providing the experience, and me for getting out of my chair to actually build this thing. here is the link to get to killerk's original page,

this gun can shoot any type of rod, but the bigger they are, the more inaccurate. i suggest you use yellow rods, white rods, red rods, or orange rods. gray rods hurt too. but they are sort of inaccurate and they twirl in mid air, so the target might be untouched or hit by the flat side of the rod.

now for the changes while firing i have noticed.
*less recoil (meaning less screwy shots)
*a smooth sound (i just love it)
*the rubber band connected to the trigger is more protected
*and i put a little green rod on the tip of the gun for a second scope
*i can finally shoot any type of rod
*it shoots through paper and sometimes even tin cans (as in soda cans)

i know a good place to get targets and print them out look at

Step 15: Gun in Action

Ok watch this video to see the gun fire and shoot through paper. the rod sometimes hits at a side angle so it doesnt go through that easily but it can. i used red, orange, and blue rods. you can use and rod to shoot with this gun.



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    54 Discussions


    Reply 8 years ago on Introduction

    I think he's referring to the jerk you feel with each shot in a powerful gun, which is, in fact, an effect similar to recoil.


    10 years ago on Introduction

    I hate this it's so $&:@;$& hard to put to gether 0stars not being mean but god waste of time if I can't put it together without cutting the he// out of my fingers


    11 years ago on Introduction

    ok tested again the gun held six bands! *pulls out two guns and breaks lightbulb* oops!


    11 years ago on Introduction

    ive got another mod (sort of) of killerk's pistol. it is strong (holds around three bands) uses block trigger, and has two handles. should i post?


    11 years ago on Introduction

    Lolz, i made a double barrel handgun using KillerK's idea of the barrell and click on ammo


    12 years ago on Introduction

    You're gonna go to jail and be good enoubh to where you order Knex out of that jail catalog, make this, and get a life sentence. Thumbs Up. Get-R-Done.Giggity Goo. Alll Riiiggghhht.

    3 replies