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The K4: Long-Range Reinvented Answered

Greetings K'nex community.  I know I have been dead for the past few days, but that is because I have been very busy working on my latest and greatest K'nex gun, the K4.

Before I start, let me just point out that when I say "latest and greatest", I mean it.  This gun is all about innovation, power, and performance.  It utilizes a new breed of pump (a slide in this case) that runs along a track system, allowing it to maintain a firm grip on the gun without getting in the way of any other major mechanisms.  It also uses a new kind of ammo, a new bow system (which is not yet on the gun) that allows the trigger to be place in the front of the gun that keeps it from interfering with any other mechanisms, and many other mechanisms that you just wouldn't see in an ordinary gun.  

At this point, it is not yet complete, the bow is still in the works but most of the more tedious elements have been taken care of.

So now I'll just shut up and give you guys a peek at the K4! 

Check out the video here


kinetic hey I've got you gun after building and he is working. it's not exactly according to your concet but work great. This is a picture of my gun I hope you like him


did you by any chance get the string a pivoting bow arms idea from my closed barreled slingshot concept? the thing is i was talking with oblivitus about making my gun into exactly that concept, keeping the winding mechanism i made. if you view the 'ible i said the problem was that the band would turn inside the barrel and said to oblivitus that if i made the bands external on a bow and have a string go through the barrel it might work. i never actually did it because i was sunk into working on something else, but i did discuss it with him and so i must ask - did you get the concept from my idea?

No, the two mechanisms are actually very different. The reason it uses a string is because the point of the pivoting bow was to allow the tension to be concentrated in the pivoting sections, not in the area where the string contacts the bullet. In otherwords, when you pull back the string, you can then mkve the string around or do whatever because it is not taught, as a rubberband would be if you were using an ordinary bow system. However, a trigger mechanism for this type of setup is goong to be gery difficult to develop because the torque exerted on the small space that the trigger contacts the pivoting arms is enormous, and thus friction makes for a very hard trigger pull.

But dude, I think you should have continued on that project, it would have been amazing. You said the band got twisted up, right. Were you only using one string to pull it back? If you used two strings, each connected to the band with about a rod's width between them, it would likely get rid of any twisting motion. That would have really reinvented long range. If you don't go back on that project, I might just have to. I'll give you credit of course.

ok first of all, they actually are similar. the original gun i posted in my failed projects 'ible wasn't very similar, but the one i talked with oblivitus about later (in the comments of said 'ible) was. never mind though. i wish you the best of luck with this project... it sounds promising.

wow, really? you really think so? anyway, since i was thinking on continuing it, since i've just entered my summer vacation and since i don't have a project at the moment, i will take on the challenge again. i thought about doing the idea with the two strings (so did oblivitus and you), but the ratchet mechanism i had built back there (the one that the string wraps around and is cocked on) didn't allow to do so without making that area of the gun (11 layers as it was) thicker. i might try a few other things i have bobbing around in my head, i might even try the idea with the two strings, and anyway i hope one of the things i try will work. i agree that it is a fresh new concept that may be very helpful. btw, on the subject, do you have any more concepts you would like to try that i might be able to help you with?

There is another concept I had a while back, I'll see if I can dig out the computer-sketch I made...

But anyways:
The reason that full and semi-autos are so difficult to make out of K'nex is because, unlike real bullets, each individual round does not come pre-loaded with a source of energy that can b\easily be released by a smaller source of energy. This could be achieved in K'ned by making pre-loaded "shells" for each individual round that would resemble cocked block-trigger guns, just without the handle and as simple as possible. These could then be stacked and, using the mag pusher as the ignition energy source, they would be pushed up continuously or semi-automatically so that the blocks release the pin and fire the bullet.

However, this poses multiple problems in the areas of bullet portability and in the loading process, as each shell will likely be awkwardly shaped. My idea is to create a cylinder that is fixed to the gun, and houses these pre-loaded pins, but not the bullets. The bullets would be housed in a vertical removable magazine that would line up with the cylinder, so that as the cylinder rotates, either by trigger pull (we could do 3 round bursts with one pull), or by a wound rubberband, the blocks in the cylinder releases the pin just as it is lined up with the bullet, firing it, and then the next bullet would pop up just as the next pin lines up and goes off.

Unfortunately I couldn't find the sketch I made, but I think you can picture it in your head. It will definitely be easier said than done, but if it can be done, I feel it will be one of the best guns ever made.

i know that thing about the real bullets... lol pretty much everybody does. anyway, your idea sounds amazing and i think i know how i can do it. wow i'm going straight to work right now (after i finish checking my comments lol) !!!

Great man, I'll start working on it too as soon as I can.

i started working on it, but there was a big problem i didn't anticipate: the rams, since they revolve and they have both a cocked and uncocked position require A LOT of space in all the direction, and that would require for a gigantic gun that would probably be weak seeing as you can't put too many bands on a simple block trigger, and it would be a pain to cock all the pins each time. i might give it another shot sometime, but for now it just seems too unattractive. i broke it apart (didn't really have much built anyway), but i can show you a drawing of what i learned should be done, if you're interested in working on this concept. maybe we could work on it together sometime.

Well, because of all that's been going on lately I have been pretty dry on Ideas lately, which is why I am so glad that TD and Oblivitus are giving us some with their new series of challenges. I suggest you look into it as well.

But, I have gotten my new rail guided pump as good as I think it will get, and I could send you some detailed pics if you want to use it in something. It isn't too incredible in itself, but what makes it good is that it is a very useful supplemental concept, as it doesn't take up space that other mechanisms could occupy. I think it could be very useful in a sling repeater or rail system repeater. I will work on that sometime soon, but I am tied up with the "slingshotgun" that TD and Oblivitus came up with. If you want to try that idea that would be great.

as far as i know, they aren't really doing much on the contests side. i say this because i was talking with oblivitus on a more than daily basis about many things, i even offered both of them a few ideas for contests, but neither of them seamed very enthusiastic about having any contest at all, so...

no need... i can see it in the pics. it's really nice, btw, i like it a lot. nice original thinking to use a silver spacer and a male joint half. i might actually use it in something. i think it could be better than the stringer loading system i wanted to use in my closed barreled slingshot. i'm not actually gonna keep on working on it because i remembered why else it wasn't very good or reliable. think about this: the wheel that the string raps around has two holes. both of them need to contain a tan clip to hold the wheel from turning under all the pressure of the band. the string has to be attached to the wheel in a way that doesn't use the holes. the wheel is smooth, so you can't just tie the string around the wheel cause it won't help. i'm not drilling another hole in my wheels. the only conceivable way to attach the string is to super glue it to the wheels, which isn't very powerful. i can't find another solution to this, but if you can, be my guest to try and build it or tell me of your solution.

A little over a week ago, TD posted The K'nex Innovators' Challenge on the forums.  It will consist of a series of challenges in which TD and Oblivitus provide a concept and the contestants are to bring it to life to the best of their ability.  Each challenge will last one week (with the exception of the first challenge), and the judges (I assume they are just TD and Oblivitus) will score each creation.  The "slingshotgun" was the first concept that they provided, and can be seen on the forum topic.

I have made a few slight improvements not seen in this forum, so if you want, I can post pictures.  As for the closed barrel sling, I get what you mean, but won't be able to provide any solutions (except add more glue!!!) without a better look at the internal layout.  But, there is a mechanism I made a few months ago that can actually "charge" a wound rubberband, or in this case, a string attached to a rubber band, bu moving a lever back and forth like in a lever-action rifle.  I can show you that one if you want, seeing that it is just lying on my bedroom floor.

ok well i didn't realize. thanks for telling me. anyway, good luck and i might attempt it myself.

i'm not gonna work on that, like i said, but i'd like to see that thing. is it the thing you made a video about and showed to me and oblivitus in the SA 3252 workspace we made?


6 years ago

Question: Is this a bullpump? It looks like one.

ok, i have to ask... did you seriously say bullpump or was it a mistake or a joke? anyway, i hope you know it's bullpup and not bullpump... lol

Mistake or not, it seems like a term we could actually use in K'nex. =P I'm thinking a bullpump would either be a weapon with a pump in front of the magazine (and thus most of the firing mechanism as well) or it'd be a weapon that is cocked via a reverse pump action (usually pulling the handle away from the front of the weapon). Depends which you think is more appropriate.

Yeah mabey I'm sure sure that would be pretty cool if that became a new thing, that i kinda started.

Sadly, if it's started on ibles, people will forget the origin of it eventually. >_>

i think a better use would be for just a bullpup pump action gun, a normal one, but nvm.

Lol TD with the save!

That is actually pretty interesting. I remember thinking of a mechanism that would actually allow you to push the pump instead of pull, and it worked out in my head and everything, but then I found your contest haha. Maybe I'll remember what it was after I unveil my take on the "slingshotgun".

Yeah its was a type-o, sorry. Yes I did know it was spelt bullpup

Developed from S0leKill3rs extended ram concept, if I'm not mistaken. That design always intrigued me, but it just broke my pieces if I tried putting enough power into it to outperform a classic ram gun. I look forward to seeing the end result.

No, I don't think so. If you mean extended barrel when you say "extended ram concept", that basically means any type of rail system. As far as I am aware, every part of this gun is completely original. Everything in this gun worked as I had designed it to, but unfortunately the effort required to actually load the bullet is greater than that required to bull back the arms. Therefore it unfortunately cannot hold a large amount of bands and thus is pretty weak. I am currently working on something similar, but will resemble a shotgun more than a bow.

Oh, ok. Parts of the rail system as well as the concept look similar to something he tried a couple of years back, that's all.


Ahh I remember that gun! I actually recreated it a while back. But yeah, he is using a rail system, just as I am here.

You are honestly proabably the best gun designer right now. The bolt action I just sent foof pics for seems so lame now, lol.

Thanks man. Well, I'm sure your bolt action works better than this one, because I am kind of stuck at the moment. Pretty much everything works, but the problem I am finding is that when you pull the slide all the way back, it is very hard to load the bullet with the extra tension of the bow on it. This may call for some major re-designing but I am hesitant to take it apart unless I am sure it won't work how it is.

Don't take it apart, I'm sure it will work somehow. How long have you been working on it?

I'd say I've put about 12 hours into it. It has been on and off because graduation is coming up and I have so much to do.

That is incredible, i cant wait to see it when its complete!

Wow Kinetic! How do you do it man?

Awesome! =D What is the new bow system like?

It consists of two sets of arms: a fixed set and a pivoting set. The pivoting arm is connected by rubber bands to the fixed arm, causing it to snap towards the fixed arm when pulled back and released. There will be a string running through the barrel connecting the two pivoting arms, so that when they snap into place, the string will drive the ram forward, along with the round. Imagine holding a string by both ends, but not very tightly so that the center droops. When you pull the string, the center snaps up. Same concept. Because the mechanism is not dependent on the release of a rubber band at the back of the gun, but rather two arms that are located at the front of the gun, the trigger can be located at the front, since that is where all the action is happening. I'll post a video tomorrow with my designs so you can get a better picture.

Isn't that a bit like your D-TAB?

Kind of, except that the fixed are and the pivoting arm are not connected. The video will be up shortly and it gives a more visible explanation.

It sounds cool. I'll be looking forward to the video.


6 years ago

Nice I haven't seen this yet.

Nice, as always :) Something you may want to consider is a Shotgun- like set-up with the Pump around the Mag. Just a thought for compacting it.

Damn I need to break this stuff out again....

Looks awesome :)

Only thing that I see is that it could probably be compacted. I dunno.

i made some of this ammo that was supposed to be kind of like a shotgun, but im not good knex gun design so i wasnt able to use it. also try putting six pairs of them on a blue rod for like a shotgun slug type of ammo.

Does it use more or less yellow conectors than the burstfire gun?

At the moment, it uses less, but the bow may change that.

Don't try too hard to innovate. You might just mess up a good concept.

I sure hope I don't, each of these mechanisms were designed to work together so if one doesn't work, then the rest are obsolete. But even if this gun does fail, I have learned more than I had ever hoped to through its construction.

Ahhh I SO love this. From what I've seen so far on the pics, it's something completely different than what exists so far. This is really a Kinetic gun.

Nice job man. It's nice to see some innovation in the knex gun industry.