Knex Sub Machine Gun.




This is a gun I made about 2 months ago. It shoots 8 green rods. The distance is determined by the rubber bands you use. I made a sub machine gun because I didn't have enough pieces To make a machine gun and I didn't have a good enough motor.
The one bad thing about it is that it does not have a trigger. If you come up with a good trigger PLEASE let me know before you post a mod.

Pic 1: side

Pic 2: front

Pic 3: back

Step 1: Make Body

Pic 1: Make 2
Pic 2: Make 2
Pic 3: Make 2
Pic 4: Make ( The long rods are yellow)
Pic 5: Make 2
Pic 6: atattch with blue rods
Pic 7: atattch part in pic 4. Also add 2 gray rods.

Step 2: Make Barral Part

Pic 1: make 5
Pic 2: add blue rods
Pic 3: add second panel
Pic 4: add block triggers
Pic 5: add third panel
Pic 6: add fourth panel
Pic 7: add fifth panel

Step 3: Add Firing Pins

This is the step where you add the firing pins. This step is also the hardest to follow.

Pic 1: make 8.

Pic 2: add orange connectors.

Pic 3: add rubber bands to firing pins.

Pic 4: put firing pins in holes.

Pic 5: atattch rubber band to the tip of the blue rod.

Pic 6: put the whole mechanism on a yellow rod, add spacers, and atattch on the orange connector.

Step 4: Loading and Shooting

To load: First do as in first pic, open up the top. Now you can spin the mec without it firing. Now pull back all of the firing pins and the triggers should flip into place if you put the rubber bands on right. (look at pic 2 (cocked)). Now put the bullets in the barrels and close the top. To fire hold the handles and use your right index finger to push down.

If you don't understand anything let me know.
Please rate



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    21 Discussions


    9 years ago on Introduction

     My conspiracy/idea for the trigger is sompthing like a lever pull thing where uzing some peices on the main axle holing the barrels you could hook up a rubber band to make the shaft want to turn in one direction. but then you have a lever(rod ?) stopping it. by pulling the lever you move that rod to a point where the shaft can and will spin freely shooting the gun. i am at a library and dont have my parts but i will build this and try to work out a trigger.

    you get four stars because the last star i didnt build it so if it runs well i will do five stars

    1 reply

    9 years ago on Introduction

    Not a SMG; by definition a SMG has to have a trigger. This is also not very original, other than possibly admitting that it doesn't have a trigger.


    9 years ago on Introduction

    This isn't sub machine gun. A sub machine gun is fed by a clip. This by looks not details is a gatling gun.


    10 years ago on Introduction

    Mayby make something like mine handling-gun / rbg !!


    10 years ago on Introduction

    its not a sub machine gun unless it is light, has a small round and is semi to full auto


    10 years ago on Introduction

    i think its good, i dont have a motor, and thats one crafty rubberband motor he built.


    10 years ago on Introduction

    Its the best one on the site thats portable and that doesnt use any cogs :D 4.5

    The Jamalam

    10 years ago on Introduction

    i suppose you could try to fit my trigger from the storm 222 onto this gun