Knex Gun: the Kinetic Rifle




Introduction: Knex Gun: the Kinetic Rifle

About: Sometimes it takes a man to push beyond what he thinks is possible before he realizes that possibility is a mere conception of the mind. Once that barrier is broken, the mind is no longer a hindrance, but his…
Hello K'nex community!

The Kinetic Rifle is finally here!  To those of you who have been waiting since christmas for me to post this I'd like to say that I'm sorry it couldn't have been posted sooner...I simply have too much going on in my junior year in high school.  For those of you that this gun is new to, here's a description of the gun and how it works:

This gun is a bullpup, horizontal magazine, pump action, sling semi-repeater.  Quite a mouthful.  The term semi repeater means that it requires two actions to load it: pulling back the band and then pumping it, rather than simply pumping it, although it has a 4 shot horizontal magazine, meaning you don't have to manually load each shot.  My emphasis on this gun was to prove the potential that horizontal magazines have, and the plain coolness of the mechanism.

So I hope you guys enjoy it and I know a lot of people have been leaving recently so I'll just say this: K'nex is not dead, innovation is just currently at a standstill.  If you decide to leave, your going to have the most amazing idea sooner or later and your going to want to come back.  There is so much left to be discovered!

*This is an extremely complex build and pictures and image notes must be followed exactly for the gun to work.  Everything is the way it is for a reason.

100ft+ range (the ratchet can hold pretty much any amount of tension so it's hard to say the exact range)

Pump action!

Much quicker reload than other slings

4 shot H-mag

Sweet reloading and firing system

Just an amazing gun


A little too big for some

Slow reload compared to conventional repeaters

Step 1: The Stock (bottom Half)

Each number explains each picture respectively:

1.  The lower stock of the gun.  Probably the easiest part to build.
2.  Build the outer layer
3.  Build the inner layer (notice the blue rods where indicated)
4.  Build center layer (notice all the white rods)
5.  Get one outer layer
6.  Attach inner layer
7.  Attach center layer
8.  Attach inner layer
9.  Attach outer layer

You've finished the lower stock!

Step 2: The Upper Stock/mag

Each number explains each picture respectively:
*This step is really long
1.  One of the unique parts of the gun: the stock/magazine.  Also includes the ratchet and trigger.
2.  The ratchet system
3.  Build these
4.  Build this
5.  Attach (I would recommend attaching with only one whit rod at first, and adding the other after step 6.  Its just easier)
6.  Attach other half.  Ratchet is complete
7.  The trigger of the gun
8.  Make these
9.  Connect with white rods
10.  Make this
11.  Attach at center.  Trigger is compete.
12.  The mag pusher
13.  Build these two parts
14.  Now build these
15.  Place them like so
16.  Connect the two using a white and a blue rod
17.  Secure with a blue rod as shown.  The mag pusher is complete.
18.  The magazine/upper stock
19.  Make two of these (one without the blue rods)
20.  Get these pieces
21.  Add them to the outer layer (take notice of the two blue spacers as well)
22.  Now make these two parts
23.  Add them as shown (this image shows blue spacers on the black wheel.  do not add these)
24.  Make this (forgot to show it earlier)
25.  Add it here
26.  Make these again (just don't add the white rod to the Y connector)
27.  Add them as shown
28.  Add the other outer plate
29.  Different view
30.  Flip up side down and break where shown
31.  Insert mag pusher and reconnect where broken
32.  Make this piece
33.  Place ratchet as shown and secure with piece made in step 32
34.  Break trigger as shown
35.  Thread through mag pusher
36.  Reconnect the trigger.  You are done with the upper stock.

Step 3: The Receiver

Each number explains each picture respectively:

1.  This is the receiver of the rifle.  Disguised as a magazine, it definitely the coolest mechanism I have ever seen in a K'nex gun
2.  The lift.  This is what you are going to make first.
3.  Make these two pieces
4.  Make this
5.  Connect the two (only 2 of the cut pieces are needed, and the receiver could be modified so that three layers of the lift protrude out of the bottom, where they could be connected, eliminating cut pieces altogether)
6.  Make this piece
7.  Place as shown
8.  Add final layer
9.  Add connector on both sides
10.  Attach tan clips on each side
11.  Make tow of these (one with blue rods and one without blue rods)
12.  Make this
13.  Add red connector with Y clip and green rod
14.  Place white rod as shown
15.  Make these (notice that the part made in step 14 is attached to one of these)
16.  Add some of the previous pieces where shown (1 layer)
17.  Add these pieces as the second layer (leave the rightmost piece unattached as shown.  Notice this piece is also trimmed short) 
18.  Add in the lift
19.  Add the rest of the pieces made in step 15 as the third layer
20.  Make this
21.  Add it here
22.  Add final layer.  You are done with the receiver. 
*Unfortunately I am not able to finish this instructable today, but the rest of the gun will be posted over the course of the next few days.  

Step 4: The Upper Barrel

Each number explains each picture respectively:

1.  The Upper barrel of the gun.  Nearly identical to that of my R-SAR
2.  Make 7 of these
3.  And one of these
4.  Get these 8 pieces
5.  Connect the parts made in steps 2 and 3 to them as shown
6.  Add connect them with green rods
7.  Get another 8 of these
8.  Connect them as well
9.  Now connect them with green rods.

Step 5: The Lower and Fake Barrel

Each number explains each picture respectively:
*This part has been modded slightly from the original version to improve efficiency, so it will look different that on the intro picture

1.  The lower barrel, fake barrel, and pump
2.  You are now going to make the pump
3.  Make two of these-one without the white rods and broken pieces. (notice the 4 white rods and 2 broken pieces. (It will probably work without broken pieces, you might want to try it)
4.  Now make this
5.  Attach it as shown
6.  Now attach the other layer made in step 3
7.  Make these
8.  Attach them where shown
9.  Connect them with the blue rod with spacers.  You are done with the pump.
10.  The lower barrel.  This part may be modded to eliminate the broken piece used in the receiver, but I am not sure if it will work.
11.  Make these
12.  Make this.  Read image notes.
13.  Connect them as shown
14.  Attach the other part made in step 11.  You are done with the lower barrel.
15.  Make two of these-one with the blue rods and one without them
16.  Make these
17.  And these
18.  Add one layer of parts on where shown.  Don't forget the blue spacers.
19.  Add the second layer of parts and the lower barrel
20.  Add the Third layer and the pump.  Don't forget the blue spacers again
21.  Flip up sight.  Make this
22.  Place it here
23.  Add the other outer layer made in step 15.  Don't forget the tan clip on the sight.  You are done with this step.
*24*  Quick fix: Remove gray connectors on each side of the middle layer and replace with a red connector that connects to lower barrel

Step 6: Putting It Together

Each number explains each step respectively:

1.  Connect the lower barrel to the upper barrel
2.  Connection points shown here
3.  Connect the upper and lower stock
4.  Connection points shown here
5.  Connection point at handle
6.  Attach a green rod here
7.  Connection points shown.  Pay attention to the connection between the red connector and the piece you just attached the green rod to
8.  Connect the receiver to the rest of the gun
9.  Connection points here
10.  And here (green connector connects between black connectors)
11.  Almost there!
12.  Get these pieces for the band guide
13.  Attach it to the front of the gun as shown
14.  Just need to add the rubber bands!
15.  Attach bands here (number of bands will vary depending on the strength of the band used as the sling.  I used two.)
16.  Another view
17.  Attach these to the lift-one on each side
18.  Attach a band to the pump
19.  Feed band(s) through barrel and over guides and hook on a blue rod.  If you are using a single band you will have to break the barrel to feed it through
20.  Top view

You are now done with the most advanced piece of knex weaponry out there.  Just don't kill anyone please.

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    Question 1 year ago

    Can you put up a piece count?

    The Knex Inventor
    The Knex Inventor

    5 years ago

    Does anyone know aproximatly how many white connectors are required to make this gun?

    The Real Phil Swift
    The Real Phil Swift

    Question 4 years ago

    Does anyone know the parts count for this rifle?


    5 years ago

    Cool! I think I'm gonna make it!


    5 years ago

    Do you need the broken part


    Reply 5 years ago

    Which one are you referring to? There are actually several in this gun, the majority of which (all but one, I believe) that are used to keep internal moving mechanisms together. These mechanisms include the pump and the pusher. For these parts, you can substitute the broken pieces with green rods, wedged in the spaces between two connectors. There is another broken puece (again, a cut rod) in the mag pusher release, and I wouldn't be able to give you any immediate substitutions for this one, though I'm sure you could figure something out.

    Happy building

    The Knex Inventor
    The Knex Inventor

    5 years ago

    Awesome gun! I will have to build it sometime.


    Reply 5 years ago

    Thanks man! As a recommendation if you do make it, you will see a lot of broken pieces in the pump and the lift. These can be replaced by putting small green rods in the gaps between green connectors, as you may have seen in other guns. This will keep the parts together without requiring any protruding rods. I haven't actually done this, but it looks like it should be possible, looking back at the pictures. You may even be able to figure something out regarding the mag pusher release. If you do let me know! Happy building, and to answer your other question, I unfortunately couldn't tell you how many white connectors it needs. Its a pain but if you really want to build it, you could count them from the pictures.

    The Knex Inventor
    The Knex Inventor

    Reply 5 years ago

    You are welcome!

    Yes, I may try replacing the broken rods with green rods.

    That's fine, I can count the white connectors from the pictures if I need to.


    6 years ago

    I want to build this =) I built the shanti bow and it was great!


    7 years ago

    I also wonder why Knex guns recoil like real ones.

    quick question, have you tried making this gun with a slightly wider pump, and having the ammunition feed through the front of the gun, and using the pump to lock the pusher for the ammunition into place, rather than having the tubular "magazine" internally built into the butt/stock of the gun?

    if that doesn't make any sense, i mean feeding the exact same way a true pump action shotgun does, but instead of it continuously pushing the rounds backward, using a rubber band attached to the beginning of the pump and the end of the mag pusher, and feeding backwards only when the gun is pumped, then with the pusher pushing the rounds upwards the exact same as the original, and in saying all that, you could attach a rotary like firing mechanism and make this truely semi automatic other than having to pull the bands back manually each time you reload.


    Reply 8 years ago on Introduction

    Unfortunately a wider pump would not be able to fit in the body of a 5-layer gun, but I guess it would be possible to just make the body a little thicker. Or the bullets could run through the pump itself, but in that case we would run into problems with the bullet guides and pusher. I have also contemplated making the pump itself the magazine (still a horizontal magazine), with an opening near the rear (closest to the handle) with a ramp pushing one bullet through a hole that is technically "closes" by the body of the gun until the pump is pulled back, at which this hole in the magazine matches up with a "hole" in the body of the gun which would lead directly to the barrel, or maybe another transfer mechanism. However this too changes the mechanism to the point where I wouldn't really call it the Kinetic Rifle any more, but it would be very effective.

    By incorporating the magazine into the front of the gun as we discussed, we would open up a lot of room in the back of the gun, allowing us to get rid of the stock, as well as open up room for more advanced trigger systems, like a ratchet system that would allow for quicker reloading. However this still wouldn't really be semi-automatic, as you would still have to pump the gun each time to load the bullet. If you are interested in a semi-automatic system of this sort, I would recommend checking out the Kinno-2, as it has both a removable rubber band magazine (sort of like a battery pack) and a removable bullet magazine.  It is a very interesting take on a semi-automatic, and also extremely effective, but not nearly as powerful as the Kinetic rifle.  If you're feeling up to it, I could maybe draw out some designs of the pump-magazine system I was talking about and you could attempt it?


    Reply 8 years ago on Introduction

    hmmmmm, i understand what you're talking about when it comes to complications about the how and why the gun is named, but names are simply labels. I'm talking about a whole new gun with an under-barrel concept in mind, i have, at the moment, this concept in mind built, but i have no idea how to or what to do when it comes to building a ratchet system for a "sling rifle" mechanism, so instead i have a standard firing pin/ram rod gun built, with the pump and arms concept build into it, the magazine running under the barrel, and i guess you could say the same "elevator" mechanism you have built into your kinetic rifle here, the only problem i had was finding a suitable "pusher" for the magazine system.

    i've seen the kinno-2 and it is absolutely amazing, definately one of the most advanced mechanism guns i've seen so far on this site. and the concept you have in mind i understands, it would be like having a magazine physically attached to the underside of the pump, with a receiver hole around the same area as the trigger (or further down the inner barrel), and some kind of elevator/pusher counter-acting the pump of the gun and pushing the round into the receiving section of the barrel, the only problem i see there, is there would be a conflicting physicality between the rear of the pump (or the intended magazine area) and the elevating system or "bolt" system made to receive the round into the "firing chamber" of the gun. The gun itself would have to be rather tall or rather oblong for the mechanism to have some kind of effect, but it is indeed quite plausible when it comes down to things like micro k'nex pieces or possibly even custom pieces of wood or a hard plastic custom made to suite the purposes needed, other than that, the questioned loading mechanism seems impossible unless you want a gun that looks similar to a sky-scraper : / but, after i post my latest ible and the concept i have built currently, i'll see how i can make this possible, worst case scenario, i attempt the same concept and build the gun wider than normal to fit the parts needed.


    10 years ago on Introduction

    Hi Kinetic.

    I just finished the gun, and I think it's awesome, but I haven't got it to shoot.

    The main problem occurs at the horizontal mag pusher(s). The two long sticks existing out of green rods and orange connectors that push the bullet into the receiver when pumped. These two sticks are not able to move forward without problems and the reason for that is, that they are blocking against the receiver part. They can't separate and move forward, they actually go to each other is some sort of way so that they can't move the bullet to the receiver.

    So actually, they collide with the middle layer of the gun.

    I don't think I explained it too well, so tell me if you don't understand and I'll take the time to explain even more.

    Greetings, H.


    Reply 10 years ago on Introduction

    I can make a video if you find my explanation not clear.


    Reply 10 years ago on Introduction

    I fixed the problem, but now I have a new problem with the lift. I can't get the right balance between the amount of rubberbands on the lift and loading all ammunition into the receiver without pushing the lift forward. When I put too many bands on the lift, it will screw up the internals in the stock, BUT then all the bullets will be loaded into the receiver automatically. When I put too less bands on the lift, the internals won't screw up, but I will have to push the lift forward manually when I shot out 2 bullets.

    I followed the instructions and I have seen your placement of the rubberbands, but if I do it your way everything screws up.

    Please help me.

    Greetings, H.