CM-10, the Mech of a Bolt-action Sling-shot Rifle





Introduction: CM-10, the Mech of a Bolt-action Sling-shot Rifle

I had decided to make a k'nex slingshot rifle with a removable magazine, and by doing that i needed to find a way to load a single round into the rifle at a time, without making it semiautomatic. Which meant the rifle needed a bolt which is what i designed. I am only posting the mech because i had to disassemble the barrel, stock, and trigger to work on another rifle, so, the barrel, stock, and trigger are up to you guys, post pictures and ill add them on the last step of this instructable so other people can get ideas. 

 - Quick reload (for a slingshot rifle)
 - Removable magazine (with no broken knex)
 - Wider body for more stability (depending on rubber-bands)
 - The mech has to have a correct contrast of rubber-bands to work well. 

Step 1: Magazine

The magazine of the gun, the rubber bands on the magazine slide should be smaller then average, but should be able to push the slide up until you can see the blue, green, and red connectors...

Step 2: Internals, and a Single External Panel

Majority of the internal mech and one side panel (clearly), I will explain rubber-band placement and inserting the magazine on the last step.  

Step 3: The Final Panel and Last Pieces of the Mech

Rubber-bands and inserting the magazine will be described on the last picture.  



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    how do you load the mag.
    i am using yellow rods insted because i dont have enough orange connecters and they are the same length as the regular ammo
    but the rods keep falling out and i can make a design that wont prevent the mag from going into the gun (im using my own gun design, if it works ill post it)

    1 reply

    The rubberbands catch upon the connector ends to shoot, yellow rods don't work.

    barrel length depends on your bands, i was using surgical tubing that was cut to fit that barrel... you could make the magazine longer, i dont feel like i need to though, i would need to adjust other rubberbands on the mech... i could improve the magazine design except ive had the gun apart for a long time now, probably not going to put it back together any time soon lol

    I'm really interested in this mech but I don't quite understand it. Could you please explain it more or take a few pics so I could understand it more? I've been trying to make a mech for a while and i think this is it. I'd really appreciate it.

    3 replies

    i have a video of it for one of my instructables, if that doesnt help just post another comment and ill see if i can help

    Oh i understand now. It's less complicated then i thought. I was trying to make it so when you pull the bolt back it cocks the firing ram (different firing mech than what you have on this gun) and loads the bullet in the chamber like you made. This is cool,

    i see where your coming from, and thanks lol...if you can manage a mech like that go ahead and post man, sounds unique

    i need to know how to make the triger barrel and the stock please

    1 reply

    its a sling shot style rifle, so make the barrel in comparison to your bands, for the trigger mech make a simple ratchet, and just throw together a nice looking can just look stuff up, i didnt feel like including the other things because if ound them easy to make, sorry for the late response.

    no idea, not too many for the mech still need to make a barrel, grip/trigger, and stock if your into that, sorry for the late response

    I made the mech then i made the other mech (i broke it though)

    thats where the words sling-shot come in handy ;)

    Pure awesomeness! 5* and a sub! I've searched and tried such a mech for months!

    forget that last comment but :
    1. how do you keep the ammo in the mag
    2. when the mag is inserted, the ammo doesnt quite reach where the bolt is.

    1 reply

    i didnt see this comment sorry lol, what do you mean by keep the ammo in the mag? and if you use some stronger rubber bands maybe? the way i had the design i had to push up on the magazine ...bullet pusher thing the last shot or two ...