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What i've been up to: the bolt action, bullpup, tube mag, pump action, dual shot, sling repeater. Got your attention yet? Answered

Ok, for those of you who had seen my shotgun design, you could probably tell it was over before it had even started.  I had tried 5 different layouts and I couldn't get past the frontmost barrel without running into problems.  I think it was a cool design, but it was just too much for K'nex.

Most of my best get designs just pop into my head at the most random times.  Is it just me, or does this happen to other people too?  Anyways I was trying to make it until the bell in pre-cal (my teacher is a crazy cat woman who enjoys talking about her imaginary husband) and I just started drawing this design.  Not only did it kill 10 minutes but it may just be the best thing I've come up with in terms of K'nex.

The magazine looking thing in front of the handle is actually the driving mechanism in this gun.  Shots are housed in the stock pressing up against the pusher.  When the pump is pulled, the pusher moves down, allowing two bullets (one shot) into the chamber.  When the pump is released, the pusher pushes the bullets up against an upper section, where they wait for the trigger so be pulled, releasing the ratchet and the rubber band, launching the two bullets with a decent (I hope) spread.  

Even though it doesn't shoot yet it is fun to just load the ammo (thats just how cool this gun it).  It is probably going to be a little different than what is shown in the video by the time I post it, but right now I'm just going with what I have.  I hope you like it and please let me know of any improvements you can come up with.



Are you going to post this cause this would be a really cool gun to make?!

Dude,the gun in the video has by far the coolest mechanism I have ever seen!!!!!!! Also,do you plan on giving this gun a name?

Thanks! I'm just calling it the kinetic rifle but I might have a naming contest for it or something.

This might just be better than your R-SAR.


7 years ago

any video updates???

sorry it took so long

kool! now i get it... =D will you be posting it this weekend?

Im so gonna build this when it comes out!!

Excellent Kinetic


7 years ago

I'd like to work on this gun with you.

Yeah that sounds like a good idea. I am running out of ideas for how the band is pushed back (I was hoping on doing it internally but that really decreases reliability. I'm also running out of pieces. I think we can really make something big here.

Send me a PM with pictures of the gun in detail and with internals if possible.

I actually think I am too close to completing the gun to start a collab, but I have an idea for a semi auto which I am not going to have the pieces to build, but I am going to work on some designs and ill let you see what you can do with it. I can still send you some internal pics of this gun if you want to start building it.

I would still like to see some pictures of the internals.


7 years ago

also, do you have to keep flicking the mag pusher catch for every shot?

No it just holds the pusher back for when your loading it.

ok cool, cant wait to make it!

New video

Now I understand how this works. It looks great so far!

Thanks! I'm looking forward to its completion.

Ah, so it's like an elevator type mechanism? I was waiting for one of these. With a horizontal magazine, these would be pretty power efficient.

Yes, this is actually the effect I was trying to achieve in the BTPA, however this is much better because it offers more room for a lack of precision in bullet placement, and allows the bullets to rise pretty as much as you need.

Hey I don't remember if I asked you before or not but I need someone who has worked with complex mechanisms and it's pretty much all you do. Think you could help me with a fully automatic RBG? I have an idea on how to make it controllable but I just haven't been able to figure out how to build it. This could be the future of war weapons if it works.

Yeah I'd be glad to work on it with you. The only way I can come up with off the top of my head would to incorporate a high to low gear ratio to decrease the speed at which the wheel spins, making it more controllable. What's your idea?

Do you know how real automatic firearms work? The concept is similar. Basically they use the expanding gasses to push a piston from near the front of the gun to recock and load the weapon. This delays the time between shots until after the last bullet has already flew out (as the gases will have to reach the piston which is usually close to the end of the barrel).

I was thinking we could do something similar with the rubber bands. There would be a band catch at the end of the gun. It would hit it and rotate to push a piston into the back of the gun. This would operate the inner trigger to automatically fire off the second round.

There are only two problems I've ran into with this design. First off, it requires a very sensitive trigger. We'd need to make it as effortless to pull as possible. You'd need to pull it by just a hair. Most old RBG triggers have it where you need to overcome the resistance of all the primed bands which simply will not work. We'd need to make it so that the trigger could "slip" out. I'm guessing this'll require a gear based mech.

Secondly, it's not quite as bad but we'd need to figure out how to make it fire on full automatic only when the trigger is pulled. Left the way as is, we'd have a sputter gun. Pull the trigger and all the shots would fire without stopping. If we could make an outer trigger device that perhaps connects the piston to the trigger so that when it's not pulled, the piston can't drive the mechanism? Whatever you can come up with.

Anyways the idea then is that the RoF would be determined by the length of the piston. The next shot will only fire after the previous bullet has already been flung.

It is a very good idea, I had actually made a sketch of a fully auto gun that shot rods with individual shells with individual rams, using the force of the mag pusher to rotate a wheel after a shot was fired, ejecting the shell and setting the next shot into the firing position. I had planned to have the mech work using the force of the rod being shot, but that greatly depletes the power of the shot. The point is that, especially with rubber bands, power cannot be distributed between both the mechanism and the force behind the projectile, but must come from a replenishable source, or else the range of the weapon will be greatly reduced. Maybe if there was a band within the gun that the loaded rubber bands counteracted while in the loaded position.

But see the idea is that the catch would be at the front of the gun. The bullet will not accelerate any more past this point. The extra energy left in the band is usually wasted into the gun. You can actually feel this in most cases. But the catch would utilize this extra left over energy to drive the inner trigger for the next shot after the bullet has already been flung.

My Idea for a true full auto, was like Kinetic's. The 'shells' with there own firing pins and block triggers, would be pushed up into the barrel. The trigger would release a hammer at the front end of the barrel. This would oush the loaded shell back, pushing up the block trigger on a light grey connector, firing the whole shell. This would push the hammer down as the shell goes through the barrel. The next round would also go into the barrel. When the other shell has left the barrel, and uncovers the hammer, the hammer springs back up and hits the next round, so on and so forth.

u could use a ratchet mech with some new twist/ innovation.

Improvements And Concerns

1. Make the faux mag as small as possible (1/3 smaller maybe?).
2. Are you sure that the dual bullets will fire with a rubber band? They may collide and go haywire.
3. Call it a slide action.
4. Make the bottom of the handle look more final.
5. Add a short fake barrel for looks.
6. Call it the "Oblivitus is the Man" gun
7. #6 is just a joke

Nice work. Math was always my favorite class to doodle in too. :)

1. It will probably get smaller with more fine-tuning, I'm just focused on getting it working right not.
2. My hope is that the rubber band will squeeze the 2 bullets together so that they travel as one until they are no longer in contact with it. If this doesn't work I will have to redesign the gun according to a single shot design.
3. How come?
4. I actually plan on having the handle reach back and connecting to the stock. This gun will be extremely sturdy.
5. This gun is going to end up being very large as it has to house a hook which will pop up when the pump is pulled in order to pull back the rubber band, and be long enough to provide a large pullback for more power.
6. I'll consider it.
7. #6 is just a joke

Haha thanks for the input.

1. Good.
2. I said that because I had the problem that I mentioned on a very similar design, so I am almost certain that it will fail, before you invest too much effort into, I suggest that you build a test rig to ensure that the bullets fire correctly.
3. Because the "pump" is on the top of the gun. Therefore it is a slide action.
4. Good.
5. Okay.
6. Yay!
7. D**n.

Your welcome.

Yeah, you were right about the firing problem, the bullets barely make it out of the barrel. I guess I am going to have to redesign the internal mech to fire one bullet, which won't be difficult, but it will take a while. And it is a pump gun, the pump is located under the barrel. Thats how the mech works: the backwards action is converted to a downwards action in the receiver. That is why there is an angled part attached to the receiver.


7 years ago

i have never seen such an innovative knex gun! 5* =D

Thank you. Thats my goal for this gun.

no problem! =D youve achieved it very well.

looks amazing! So you're actually going to post this gun? (if it works?)

If this works, and I fail to post it, I will personally send you my address and a pair of jumper cables. I am going to post it.

i agree with Oblivitus, make that long mag like thing in the front a bit shorter.


Hell yeah it is! Haha thanks.

This looks pretty good!

That is a great idea, it could be connected to the trigger to that it would lower when the trigger is in set position, then lifts the ammo as it is pulled, then another connection would release the pin. This would be an excellent idea in a gun with a magazine under the barrel rather than the stock. This is an excellent idea, however I don't think I can apply it to my idea, as the gun is near completion. I really hope you can turn this into something. If you don't then I'll give it a try sometime.

*yay 1st comment*
Looks amazing, I don't think anything like that has been done before at all, so good job I can't wait for it!