Author Options:

An idea that mite make knex semi auto. Answered

for the average knex gun, you need to cock it everytime you pull the trigger. couldnt you get a giant fat spring that could act as extra recoil? if you made a gun with a short firing pin and a few bands, with a strong and long spring, dont you think it might be able to be semi auto? If it did work eventually afta about 5 bullets the power would be lost. but still it could work? maybe not sure.


that will not work because the firing pin is tensioned to a higher amount then the spring and so the spring will have to release its force somewhere so the gun will most likely self-destruct.

Are you saying you'd just let the firing pin bounce back and forth? I was thinking that you were saying there'd be enough recoil just to let it get past a block. Just a thought. And yes, I realize this is a dead topic.

I doubt it would work. Machine guns work because the force pushing the bullet (the explosion) goes away as soon as the bullet leaves the barrel. Then the spring would push it back.

there could be a gearing system using the newer knex parts and make a transmission-like system so it could be powerful enough to shoot with enough power.

with air soft guns there is a motor to pull the firing pin back to the beginning once fired. maybe we could utalize this reload systam to make a gun with knex?


10 years ago

I tried something similiar. If you have enough opposite strenght to pull the pin back, it won't fire. Semi automatic systems are limited with K'nex, I think the best solution is a pump action. I've had a big idea for a pump action gun for a while, but haven't gotten around to trying to build it yet. If it works as I hope it would be similiar to Perfect Ducks Red Impact ( E.g, frictionless louding ), only with a pump action, and more reliable. It's complicated though, and seeing as I'm not super experienced with designing it will take me a while to realise if I ever start it...

hmm, I have thought about this kind of mechanism for a while. It won't work. As soon as the pin is released, if the spring is too powerful, then it wouldn't fire again. If the bands are too powerful, then it won't bounce back. If they are even, then the ram will be halfway in between.

possibly, however, knex is far from an ideal tool for building this type of device, it would probably only work from 2 shots at most.