K'NEX 40 Mm System V 1.5

About: K'NEX gun builder here at Instructables. More or less retired from the community, but I still pop in now and again.
Hey guys. Well, this is a new type of gun to instructables. It is "commonly" known as (or rather, not so commonly as) a 40 millimeter (mm) system. To learn more, see here. 40 mm systems are grenade launchers that, hence the title, shoot 40 mm grenades. The Mark 2:20 is a full-auto 40 mm system, and is found in many of the CoD: MW games.

Mine is a is a K'NEX version of a 40 mm system, but is not, technically, a replica of any particular gun. I just thought it would be cool to bring up a new "concept" to the K'NEX community on instructables.

Looks kinda cool (IMO)
Has good range for a grenade launcher: 40 ft.
Has good close range power
Easy to handle
Has a pin-guide (you are welcome Knex.X) XD
Has detachable mag/inner barrel
Can shoot shotgun shells
Has handle guard
Might be useful in K'NEX wars
Has true trigger

Trigger needs some help to block
Not a replica
Kinda difficult to load

Well, there you have it. The R40mm System. I would really like some of you guys to really just take this and use it to your advantage. It is my gift to you all. Have fun modding and looking.

-The Red Book of Westmarch

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    53 Discussions


    1 year ago

    hey could you make instructions or at least show internals plz?


    5 years ago on Introduction

    Are you sure another rubber band wouldn't fix the catching problem? I don't know exactly how it holds the ram, but "push it up a little bit" sounds like something a rubber band would help. BTW, are there instructions?


    6 years ago on Introduction

    Awesome. That is all. Jk really cool idea dude... See? You do have it in you to make some concept guns... Anyway, I can think of at least one thing I see that'll increase the range at least by 10 feet or so, but the way I know you, you probably don't have it built anymore, do you? Again, awesome idea, cool execution, good looking, slick gun. Awesome. That is all.

    5 replies

    Thanks man, I am glad you like it. Well, I guess that I never really considered this as a concept gun. It really was just a way of me building a lazy version of a shotgun. No, I don't have this built anymore, but I am definitely considering building it again. Thanks for the complements, and it is good to hear from you. =D

    It's not a concept gun in the same way as my guns were, but it's definitely a start... Yeah I did kinda lose interest in knex... again... Sadly, I think this time it might be for good...

    That is true enough. Well, don't jump to conclusions to quickly, I have had my ups and downs with K'NEX, at one point I thought that I could not build anything, and look where I am now? I have 75 subscriber, 43 'ibles, and over 14,000 views. On top of that, I have over 30 Favorited ibles, and I have gotten the attention of the play-editor here at instructables, not even to mention, some of the best K'NEXers here. If this counts as bragging in your opinion, I will delete this comment, but the point is, you'll come out of your doldrums. I am in the midst of a doldrum currently, as I cannot seem to get my flipping MP5SD to look right. It has a semi-complicated mech, and is some-what correct. I would like to post it next Sunday (the 19th of May) because that is my one year anniversary. One year ago next Sunday I posted my first 'ible. It was a VERY bad version of the MP5SD (look below at first pic). The second pic is the one I am working on, and the third pic is a real one.

    IMAG0186.JPGDSC08639.JPGMP5SD 6.jpg

    It's not that I don't think I can build... I just don't want to... I haven't touched my knex since I think December and I don't miss it in the slightest, which never happened before... And it's not a matter of depression or anything it's just I have much better things to do nowadays and I don't find building as fun as I used to... I might just make one last parting gun in the summer, but I'm not even sure about that... Yes you have grown a lot since the beginning, and I feel stupid for being that little brat I was a year ago that picked on you -_- lol this past year changed me a lot... But I guess that's growing up... Lol...

    Ah, I see. So, you don't miss your K'NEX at all? I bet they miss you. (XD I am teasing). Well, don't worry about it, its not that big of deal. I know its not a matter of depression, that would be a silly explanation... Well, I may have grown as a K'NEXer, but, as of yet, I am not as experienced as I would like to be. That'll take time though. I would not say that you were really a "brat," you were kinda rude, but that was EXACTLY what I needed to get better. =D