Knex Powerful Semi-automatic Gun




Posted in PlayKnex

Introduction: Knex Powerful Semi-automatic Gun

About: Umm.. My name is Louis and.. oh yeah, add me on XBox, my Gamertag is ConfusedGiraffe.

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

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

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

Step 4: 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.



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    This thing has the potential to be a ballistic knife

    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 ^_^

    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!

    1 reply

    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 =/

    one of the best guns on this site!

    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!

    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?


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

    I got it to fire without any rubberbands

    I have extended the mag to hold 18 shots 5 star

    this gun is awesome must has more

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

    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.

    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.

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