Failed Knex Gun Concept - CQB Assault Rifle




Introduction: Failed Knex Gun Concept - CQB Assault Rifle

About: Hi. I've sold off about 99% of my k'nex, but I still come here to check in on instructables, every 2 weeks or so. I like seeing what's new in the k'nex, and also other sections. I may or may not post my K'n...

I normally don't make concept guns, but I decided to see if this one mech I thought up would work. It works by having a ratcheted elastic powering a rotating firing pin. It all worked out on paper, but when actual building came around; this gun failed to shoot. But I was satisfied that the mech was possible, and functioned at all. I did take pics of the "completed" gun for you all to see. 

This gun on paper would have shot 25ft at about 300-500 rpm at an estimate. 

Now for the pics of the gun below.



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    27 Discussions

    Haven't posted for ages!

    2013 11:47 PM.jpg

    I just finished up with my full auto smg that is gunna run off a drill. Its been a prototype for a few months and Its gunna be awesome. Even though it only has a range of 25-30 feet. It shoots oodammo which makes the range quite decent.

    1 reply

    Do not post it here please. That doesn't have anything to do with commenting on *this gun*.

    so this is an SA 3252? it's not new man, you didn't think it up. also, i made a much better version that did work.

    Cool gun man. Kind of based off of Oblivitus's concept? I made something a few months back that is kind of similar. I'll see if i can dig it out.

    Yeah, im going to get 1000 knex pieces for my birthday in 3 weeks so I can invent better things!

    2 replies

    Have you figured out which part causes it to fail to shoot? I think that you could get at least a little more power out of the mech if you used a drum instead of a raw axle; two circles with 8 white rods connecting them would give the bands MUCH more power to actually move it.