Introduction: Fully Automatic Knex Gun (UPDATED)

Picture of Fully Automatic Knex Gun (UPDATED)

This gun is based off of bakenbitz idea and i just improved it and changed it around. Its fully automatic. It works by cranking. I made this gun to shot airsoft bbs but thats just because i like that so u can make it shoot something else if you like. It probably shoots about 3 or 4 per second. It comes with a clip that holds about 23 bbs. If enough people ask for the instructable than ill do it. It still needs some work but it doesn't shoot to far but its a brand new design and there is nothing else like it that i can find. hope you like it. please comment on what you think about it and if you upgrade it please tell me thanks.

don't forget to rate and comment

connectors-6 double gray connector
-12 green connector
-26 purple connector
-12 blue connector
-77 single gray connector
-1 ball joint connector
-29 yellow connector
-36 black Y connector
-8 orange connector
-27 red connector
-19 white connector
-11 brown rod connector

-87 green rod
-32 white rod
-26 yellow rod
-5 long gray rod
-1 blue rod
-3 red rod

-2 small gear
-2 big gear

-10 gray spacer
-19 blue spacer


i made a real semi auto knex check it out



hey everyone,
check out my youtube page

Step 1: Body

Picture of Body

make this

Step 2: Barrel

Picture of Barrel

this is the barrel

Step 3: Crank

Picture of Crank


Step 4: Clip

Picture of Clip

sorry it is a little blurry

Step 5: Ram

Picture of Ram


Step 6: Handle

Picture of Handle

this is the handle

Step 7: Stock

Picture of Stock

the stock

Step 8: Add It All

Picture of Add It All

ur done


Knexmaniac543 (author)2017-05-30


andrew.cobill (author)2015-04-29

EpicMinecrafter870 (author)2015-04-28

You tell us not to make this gun yet you give us instructions.

wezils tuts (author)2014-04-09

what's the range

www139 (author)2014-04-01

Looks cool! Can't wait to build it!

Jasp3r (author)2008-05-29

I've only got a little gear without tan connector hole, so mine slips cuz it isn't attached to the axle. How do I solve that?

TheKnexDemon (author)Jasp3r2011-07-27

Get two stub connectors (small blue things with no hole) and try pushing them close up to the gear

if u use the tan ones with the stubs on them u can connect them in the small holes in the sides of the gears

But then when the gear rotates, it would be blocked by that tan connector which would cause many problems

Katarukito (author)Jasp3r2008-10-28

super glue

chasm (author)Jasp3r2008-06-05

You can't

XxsonicxX (author)2012-04-03

I need t say this... i isn't fully automatc, its crank action

dutch ghillie (author)2012-02-27

the grey clip is broken a clip to hold the bb's

danroy99 (author)2011-12-23

Does it work with metal bbs?

arjun1 (author)2011-12-16

does not work

jake scythe (author)2011-10-23

it is basicly a gattling gun in rifle size

donnie2 (author)2010-10-31

mine wnt work no matter wat!! :(

TigerNod (author)donnie22010-11-21

As the description says, it's a prototype. I built it too, it is very unreliable.

qwerty987 (author)TigerNod2011-02-01

when i built one it would blow up in my face every time but i will try again. it is ok if you make fun of me for it blowing up.

TigerNod (author)qwerty9872011-02-05

Ow..... That's... Unfortunate.

I won't make fun out of you. It is a commonly known fact that most full-auto's have a tendency to blow up.

ryanreers (author)2010-12-28

if you switched the gears they crank would turn faster

Sketch98 (author)ryanreers2011-01-27

but there would be less torque causing it to struggle under more rubber bands

knex1111111111 (author)2011-01-19

I added a motor instead of the crank and it became automatic.

flyerminer (author)2010-10-10

plz find out a way to just use knex ammo and not airsoft bbs! it'd make meh happy. =D

Spycrab (author)2010-08-17

the 'airsoft bb's' thing disappointed me :\

Blackbird17 (author)2010-08-16

sry but i took this apart along time ago. we are moving soon so i cant do anything soon sry

Blackbird17 (author)2009-06-19

i can add a barral to shoot green rods if u want

ellis-perks (author)Blackbird172010-08-07

could you plz send me some pics or a clip on how todo this. thanx

sukinmaru (author)2010-07-31

cool, you ought to make a Mulcher from GoW2

Merugop (author)2009-07-31

Oh yeah what are those grey parts in the middle

Abcwtfidontcare (author)Merugop2010-07-12

Those grey parts in the middle of the barrel are 3 tan clips.

anres321 (author)2010-07-05

hey I have made a fully automatic knex gun that works with a totaly diffirent system that is never used before on a fully automatic one. So would you plz tell me wath you think about it ?? here is the URL:

snow clones (author)2010-06-20

Great gun; try making a high mag, high power, bolt slingshot sniper! I've made one and it goes about twice as far because you use a bullet that slides on the rail, and the power is a slingshot.

pokemonguy123 (author)2010-04-26

i have seen it on you tube im paranid630

joelyboy94 (author)2010-04-14

 Your photos are fine and your guns wicked, but you mite find knex mlcad useful - there are quite a few annoying flaws in the program because its pirate, but if u manage u can make decent images and instructions. im not gonna lie its hard but tell me if u want the program

smattman22 (author)2009-07-29

mine wont fire or pull back far enough.

you must of done something wrong than

i have thick rubberbands. but it doesnt slide all the way foward

I know what you mean. You've gotta add spacers (not connectors or there will be blocking something) here:

i dont know what to tell you. try less rubberbands

Buckethead32 (author)2010-03-25

your photos arent showing up on the screen but other guns are.  Do you know what that is

robb45 (author)2010-03-23

i made this gun end it sucks wen i want to crank it brokes

robb45 (author)2010-03-23

very cool gun does the mag works good?
i gonne make this gun now

snwboy123 (author)2010-03-06

you should make more steps for  num 2 but besides that its great

bio-logical (author)2010-03-01

hi i'm just wandering what knex sets you would need to make this because i can't buy individual pieces please help and i live in australia

The Knex Builder (author)2010-02-22

 Please Help I fixed the problem I commented on, but my gun only shoots 2 centimeters at best.  HELP!!!!!

rustymia (author)2010-02-21

 Thats not a fully auto gun a fully automatic u just pull the TRIGGER, witch yours doesnt have, and it fires everything in the magazine

The Knex Builder (author)2010-02-20

 Please Help!!!  I built it and the firing pin won't go back far enough to let the BB in.  HELP!!!!!!!

GeekBeam (author)2009-10-24

hey extreme builder im going to attempt to mod your full-auto knex gun to shoot rods using your 12shot mag design if i cant post it than try it out,it might lead to yayness

BuilderLoon (author)GeekBeam2010-01-27

ROBLOX!!!! I quit... i got ubuntu ... no more  microsoft :(

About This Instructable




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