Simple Knex Gun With Mag & True Trigger

This easy to make knex gun has a mag as the handle and a true trigger. It fires grey connectors and is also good as its quite compact.

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Step 1: Outer Layer

This is the outer and first layer you need to make. Two will need to be made but only make one for now.

Step 2: Middle Layer

This is the barrel and the mag and the trigger system instructions. They go in order and parts that look broken need to be like they are shown !

Step 3: Last Layer

This is just like the first layer but assembled in a different way.

Step 4: Final Touches

Last bit add ons and you may want to compare pictures to guarentee a copy.



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    13 Discussions


    7 years ago on Step 2

    do they have to be broken to work what will happen if they aren't broken

    1 reply

    Reply 7 years ago on Step 2

    The broken orange piece allows the firing pin to fit into the barrel, and the half green piece stops the trigger from catching on the lip of the orange piece it's connected to.


    7 years ago on Introduction

    how far does it shoot because i live in a small town and quite a few kids have knex actually not very many of them are kids most of them are around 13 and we all love new designs


    Reply 9 years ago on Step 1

    The Y connectors are needed as the handle needs to be big enough for the projectiles to fit in. you might not need them if you use green rods for bullets but you will have to mod the barrel possibly.

    DJ Radio

    9 years ago on Introduction

    Not a very good design.  First of all, the trigger is way too far up the barrel, causing a major loss of power.  The mag behind the trigger reduces it farther.  

    5 replies
    joshbleaseDJ Radio

    Reply 9 years ago on Introduction

    I have realised certain problems with this gun but it is my first and i'm not the best designer of guns but thanks for the advice.

    Mr. Mugglejoshblease

    Reply 9 years ago on Introduction

    well, that's good, most people are only angry when other people give them criticism, it's good that you're not one of them

    DJ Radiojoshblease

    Reply 9 years ago on Introduction

    I have a feeling you're gonna become a good knexer one day.  What Jamalam said, only the ratings aren't that reliable.  There are pretty much a few guns anybody would recommend, here are my top picks (I'm not gonna be biased and include my own guns, but they are worth a look):

    - ZKAR
    - TR8/TR18
    - Knexsayer
    - NAR (also known as Untangle)

    Take some innovation off these guns and learn from the building techniques.  Try putting these into your own style and use that style to come up with ideas, and then to turn those ideas into reality.  For reference, I cook up ideas at least 2 weeks before I actually build anything.  I spend those weeks developing ways to construct the gun.

    The Jamalamjoshblease

    Reply 9 years ago on Introduction

    What I'd reccommend is building stuff from the top 5 rated pages. Getting that experience and seeing how innovative designs work will really improve your own building. Also check out pretty much everything on here: