Knex Arm Cannon

About: Hello! I'm Nerfrocketeer, also known as Nefrock', Nerf, or NK. I am an avid fan of Nerf wars, engineering, and animal activism (but no I don't go overboard). Thank you for A MILLION views (woah!) and making ...

This is my newest knex invention: the arm cannon! This compact weapon is worn on your arm, and is fired by a quick downward flick of the wrist. It has great range, but is a little hard to prime. I will make some modifications to it, and post it later. Thanks for viewing! Please comment!

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    11 Discussions

    It's okay for one of your first k'nex guns, though, to be honest, these kind of weapons are pretty outdated. How much k'nex do you have? Maybe you can try building some of the higher rated k'nex pistols on the site (such as this one). That way, you can get an idea of good trigger mechanisms and such. 
    Keep it on

    4 replies

    Well the first box I have is a 700-something piece box... I haven't built anyone else's guns because either they require broken pieces (and I don't want to break mine yet... They're new..) or they need pieces that didn't come in the box...

    Also thanks for that link! It looks buildable for me. I still need to get the hang of knex since I usually make stuff out of raw materials... I.e. the shotbat...

    No problem :)
    K'nexing in the beginning can indeed be a bit 'complex', but you get the hang of it pretty fast, just keep building ;D


    6 years ago on Introduction

    Nice! Maybe try to make sure the gray rod isn't bent by the rubberband. This will allow the ramrod to be pulled back easier and come forward easier.

    1 reply