Introduction: Knex Powerful Semi-automatic Gun

This is a gun I made which was originally a grey connector speed reloader, but I modified it into a powerful gun. It has 6 round cap, but I might post a 23 round cap version sometime, if you can't work out how to (just extend, and replace the yellow push rod with a grey one). To fire push yellow rod up until it fires.
Semi automatic
Quick reloading
Low piece count
No trigger (push rod to fire)

Step 1: Piece Count

Please correct me if I get it wrong.

Green - 7
White - 12
Yellow - 1

Yellow - 8
Orange - 4
Dark grey (excluding ammo) - 4
Red - 4

Black Y-clips - 2
Elastic bands - 1 needed, 2 wide ones recommended, you can use just like 10 quite thin ones

Total (excluding bands and ammo):

Step 2: Magazine/grip

Picture of Magazine/grip

More or less the whole gun. I will help if necessary.
9. The white rod doesn't clip in to the Y-clip, it just rests there

Step 3: Other Parts

Picture of Other Parts

The firing pusher thing and the thing to stop round falling out. The instructions are simple enough I think.

Step 4: Loading+firing

Picture of Loading+firing

1. Attach rubber bands.
2. Load the rounds. It doesn't matter which way you load them, but the way the are loading in the photo makes them fly straight. The other way makes them fly slightly up. It doesn't improve range, just if you may want to hit something behind e.g. a sofa.
3. Push the thing I'm pushing in the photo.

If it is not powerful enough add elastic bands until you get the desired power. The more bands, the harder it is to fire.


tinyhooman (author)2016-10-29

This thing has the potential to be a ballistic knife

Larscool (author)2014-03-24


Smiley_Face (author)2014-01-02


Louis XIV (author)2012-10-08

Hi guys, I thought I'd log in for the first time in about 3 years haha, 17 now, thanks for all the comments :) I don't do Knex any more I'm afraid, I'm focusing on music these days but I hope you've enjoyed what I've left ^_^

Endermanman7 (author)2012-08-27

If you push the yellow rod up (or down, depending on wich way you hold it up) really fast then it sorta becomes a fully auto gun!

SumRndmGuy (author)Endermanman72012-09-06

ok if somebody will make this into a gun with trigger and stock and barrel, and everything tht makes a gun a gun (obviously) i would love to see it, believe me...ive been trying insane amounts of my time are going into trying to do it...and its not working =/

rlaxrlax (author)2011-09-19

one of the best guns on this site!

Killer~SafeCracker (author)2011-06-03

I dont think you're still on the site which is really sad seeing that YOU started new era of knex. This gun, as simple as it is, is becoming the basic blue print for semi auto knex guns. You should be quite happy!

mberg (author)2011-05-28

behold! i give you! the powerful knex semi automatic gun 2!
i made a bigger version. it holds 8 more bullets (14). i can't make it any bigger. is it ok if i made a youtube video about it?

qwerty2008 (author)2011-05-13

I have found several ways to make this into a removable mag.

qwerty2008 (author)2011-05-13

I got it to fire without any rubberbands

qwerty2008 (author)2011-05-13

I have extended the mag to hold 18 shots 5 star

qwerty2008 (author)2011-05-13

this gun is awesome must has more

TheFoofinator (author)2011-01-13

This is officially the mystery gun- I cannot explain hoe this thing works!

fortheheckofit (author)2009-05-26

18 round fully-automatic uzi anyone? >=D

maybe you can put a trigger that will stop the fire then when you pull it down, it with blast all the rounds because the mag pusher has too much force on the bullets and when you release the trigger or pull it down, the rounds will fire like crazy

too bad it isnt fully it? if it is i bet it goes 2 feet.but i doubt fully auto

yea, it's an extended version of louis's gun which holds 18. i just added a frame to make it look cool =D. btw, it shoots like 20 feet at like 10 rounds/second, lol.
Too bad it doesnt have a trigger.

Louis XIV (author)combatknex2009-06-17

If it's using the same system as mine, then it is fully automatic and has more or less the same range. You just push up on the follower thing and it'll keep pushing rounds out.

lemonpickle (author)2010-12-05

when i fist saw this I thought it was a piece of crap but now that i made it its awesome 5*

MegaMetal8 (author)2010-12-02

WOAH, built it. I LOVE IT 5* AND SUB

KnEx_MaStEr (author)2010-12-01

this is a true semi auto cool!!! i built

skelly7447 (author)2010-07-27

best gun on the site!!!!! P.S. leave a reply if a knex gun has ever exploded on you

st j (author)skelly74472010-08-11

i am canadians SPIFF exploded, the magazine did a dump and it hurt my fingers

skelly7447 (author)st j2010-08-25

i am canadians striker pistol, actually my modded version. Striker rifle exploded. whole barrel flew off. it didn't hit me but the thing wayed like a half pound and it flew backwards like 20 feet

nickpkcin (author)skelly74472010-08-31

some oodammo gun, cant remember which. got the mag wrong, and when i fired the whole thing blew up in my face.

inergy (author)nickpkcin2010-11-23

dun no name of gun but it was a sniper and i aimed it right at my bro's head and i pulled the trigger and the whole thing blew up in my face.

RMConstruction (author)2010-11-16

Oh COME on! No offence, but how the heck did this reach the first page?!

DJ Radio (author)RMConstruction2010-11-20

Because it introduced a brand new firing mechanism that was never done before in knex. It is very innovative.

RMConstruction (author)DJ Radio2010-11-21

I stand, corrected.

skyfaller (author)2010-10-15

You could take the bottom of the thing you push, and use it as ammo. Place a single slot small blueconnecter to replace it.

skyfaller (author)skyfaller2010-10-16

Sorry, I meant blue clip

claytonjai (author)2010-09-24


claytonjai (author)2009-07-26

wot's a Y-Clip?

KnEx_MaStEr (author)claytonjai2010-09-24

a little black conector about roughly 1cm

danbaha (author)2010-08-30

Very inovative!

hazza the gun (author)2010-08-12

nice little design. 5 star!!!!!!!!!

fatbubbleman (author)2010-04-29 i did that upgrade you sad by building it bigger and i shot it and it fires twice as far...also i pushed it completely to empty the mag  and shot over 20 bullets in less than one second

SpeedStrikerXLR (author)2010-04-19

 Omg I love this thing i just built it and shot it and I first accedent ly shot all or them at once!!!!!!!! love it

~Z~ (author)2010-02-24

 Wow. Nice! 4.5*

The Jamalam (author)2010-02-23

I might mod this for a full gun.

118118 (author)2009-11-10

This is the best gun ever!!!
it's easy and its awsome
i thank you for building this
youve nearly got full auto :)

mettaurlover (author)1181182010-02-06

If he adds a strong RB to the yellow rod and a white rod to the red connector o nthe front to keep the ammo back, he'd have full auto.

Sasha25 (author)2009-12-20


X19OV1 (author)2009-06-25

I've modded this gun so the rod comes from the side instead of the bottom, so you don't have to worry about that anymore. There are a few other noticeable differences, but they're not too important. I'll post the mod if enough people ask for it.

Chikara (author)X19OV12009-09-29

a little late, but would you please just post a picture? im interested in it

X19OV1 (author)Chikara2009-11-14

Sure, but I have to build it again.

Chikara (author)X19OV12009-11-26

almost done building it? ;)

Chikara (author)X19OV12009-11-14

coolsauce, thanks

KnexFreek (author)2009-11-11

i dont get it..... so im gunna build it to see how.
ill tell u how it went when im done.

About This Instructable




Bio: Umm.. My name is Louis and.. oh yeah, add me on XBox, my Gamertag is ConfusedGiraffe.
More by Louis XIV:Knex G3 SASKnex powerful semi-automatic gunKnex powerful semi automatic gun
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