K'nex Semi-Automatic/Repeater/Shotgun

Note: By reading this, you accept the "Terms and Agreements" below.

Terms and Agreements:
Any pain inflicted by this "gun" or by your own idiocy while attempting to build the "gun" is not my fault. Deciding to shoot your friend/your toy/your pet/yourself is your decision and your decision alone, though there is always the influence of others. I cannot and will not accept responsibility for your actions, unless I, in any way, shape, or form influenced you directly within a distance of 10 yards (9.144 meters) of you to shoot your friend/your toy/your pet/yourself, etc.This is not a toy. This is a potentially lethal weapon.

This "gun" is built from two parts: the magazine/feed and the barrel (ram included). A couple of things you will notice about this "gun" are that it has no stopper/blocker/whatever the thing is called that stops the ram; it jams readily if not fired correctly (and if you just aren't lucky, but it is easily unjammed); by shotgun I mean 2 bullets at a time (you will realize how annoying this turns out to be later); and, finally and most importantly, the magazine is detachable (meaning you can remove it and attach a fresh one instead of having to constantly reload!!! OMGZORZ!!!!).

Note: Any list of required pieces is the list of pieces I used to build my version of the "gun." Certain pieces can be exchanged for others.

Special Thanks to: (your name here), an actual Instructables username, for the amazing magazine design. You will notice that I modified it slightly.

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Step 1: Constructing the Barrel and Ram

This is the easy part.

1 black rod
1 tan clip connector
1 red connector
1 orange connector

2 yellow rods
1 red rod
8 orange connectors
7 red connectors
2 grey connectors
1 white connector

The ram is self explanatory.

For the barrel, just attach the many pieces onto the single red rod.

Please excuse the blurry pictures.

Step 2: The Magazine

This is a hard one, but without it, you can't fire anything. Again, props to (your name here) for the amazing magazine design.

Outside: (Pictures 1-4)
21 green rods
6 white rods
14 yellow connectors
6 orange connectors
2 red connectors
2 grey connectors

Inside: (Picture 7)
2 white rods
1 green rod
2 red connectors
8 blue rods (recommended amount of ammo per reload/magazine)

Bottom: (Pictures 5-6)
3 green rods
2 yellow rods
4 tan clip connectors
4 green connectors
4 red connectors
4 light gray connectors

I will show you how to build it in three parts: the outside, the bottom, and the inside. The inside is just the ammo and the auto feed. The outside and bottom are the important structures.

Just follow the pictures.

Step 3: Firing

This is the simplest thing ever. Just pull the ram back a significant distance back (but not so far as to have it leave the barrel) and then release. Because there is no ram stopper thing, this gun comes with rapid fire capability! That's good and bad. It's good because, well, it's rapid fire. It's bad because as the magazine holds such a limited amount of bullets and because the gun fires 2 per fire, the magazine is depleted extremely fast, forcing constant reloading/switching magazines.

Step 4: Jamming and How to Fix It

Jamming is the probably the most annoying aspect of the gun, second to the necessity of constant reloading/switching magazines. The bad part about it is that it happens very often and most of the time, you don't realize it until too late. The good part about it is that this problem is very easy to fix.

Jamming usually occurs when you are rapid firing (which you should be) carelessly (which you shouldn't be). There are 2 tell-tale signs of jamming. 1, if a jam occurs, only 1 bullet is fired. 2, the ram does not have the ability to be pulled back into the barrel, unless you really force it (which you shouldn't do). If you look at the front of the magazine, you should notice that a bullet, the one that was not fired, is trapped under the ram, preventing the ram from leaving the magazine.

If you realize there is a jam immediately, then the front of the magazine should look like the picture below. This is only when you've just fired, realized a jam occurred, and haven't fired again. Usually, when you're rapid firing, you don't realize there is a jam until you notice that nothing is shooting out. When this happens, the bullet trapped underneath the ram probably has been pulled back.

Either way, all you have to do to remove the jam is to expose the bullet so you can get a good hold on it, then pull the bullet out.

Step 5: Attaching/Detaching/Reloading

This is pretty simple. The pictures should say it all.

#1-4: Attaching
#5-9: Reloading
#10-13: Detaching

Step 6: Conclusion

Now that you've built your nice Knex Semi Automatic Shotgun, bask in the glory of your great accomplishment. Then shoot people, massacre people, terrorize people, and pwn people. Just make sure to be safe. Read the Warning again if you refuse to comply with that last statement.

Have fun!



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    93 Discussions


    7 years ago on Step 2

    where does the last 2 orange and 1 green rod go together?

    not semi auto
    semi meaning pull the trigger back and firing and auto meaning when the trigger is replaced at its place it has reloded automaticly !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    Mr. Dudeness

    11 years ago on Introduction

    Well if its a potentially lethal weapon, why build it? If I wanted something lethal, I could get my dads real 12 gauge shotgun or just use my compound bow and kill something. Now that's lethal.

    10 replies

    Honestly why would you play with knex at your age. No offence or nothing. Its still cool though. But sad aswell.

    xiao hawkMr. Dudeness

    Reply 10 years ago on Introduction

    Well your dad's real 12 gauge shotgun is potentially lethal too. All knex guns and all weapons for that matter posted on this website are potentially lethal too. Why build those? Because they're more potentially lethal than this one. So please stop wasting your time and my time here.

    NinJa_RaiZerxiao hawk

    Reply 10 years ago on Introduction

    potentially lethal??? sure. my best gun shot at like,i dunno,40 feet. If an airsoft gun at 300 fps. fires spherical rounds of about .2 grams 175 feet with a 11 gauge spring.i doubt that this could fire a round of like 4 gram rods hard enough to kill anything,but,hell, what do i know?


    Oh jesus, I really didn't mean to start a big debate about all this, I completely forgot i had that comment and people are still replying 3 months later. Wow. Um, yea you go with your conversations then,i probably wont be replying anytime soon.

    DrWeird117Mr. Dudeness

    Reply 11 years ago on Introduction

    and i could simply get my OWN (yes, it's legal to own one) PS-G1 converted(by me) to fully automatic.

    An Villain

    10 years ago on Introduction

    for #2 it is potentially lethal, here is a list of how it could be potentially lethal: you could beat someone over the head with it, you could stab them with a sharpened firing pin, young children could choke on the small parts, and they could be shot repeatedly until they go insane and go jump off a cliff somewhere or something. and it is semi auto you just have to add an orange connector to the firing pin and call it a trigger, then it could be semi auto. and who cares about looks? he only called it a shotgun because it has a spray.