K'NEX Gun: SMRI Infantry Automatic Rifle / Short Barrel Rifle

About: K'NEX gun builder here at Instructables. More or less retired from the community, but I still pop in now and again.
The Simulated Modular Rifle Initiation (SMRI), so termed by myself but invented by TheDunkis, was originally intended to "look realistic but otherwise was [intended to be] completely nonfunctional." When I first saw the forum topic, I was immediately impressed with how it looked, but at the same time, I was wondering how it would look were it modified to shoot. Taking over 1 month to build and improve (I went through at least 6 different versions), my  SMRI can not only shoot, but has numerous other features, things such as:

- Great range: 40 - 60 ft.
- Really nice sights
- Super modular body
- Preloadable magazines
- Extendable stock (gun goes from 28 in. to 32 in. SBR version)
- Ability to change from IAR (Infantry Automatic Rifle, Pics 1 - 12) to SBR (Short Barreled Rifle, 13 - 22)
- Really easy to operate, un-jam, and modify

While a number of us worked on the gun (TheDunkis, didexo, and myself), only didexo (see his version here) and I were happy enough with our versions to post, all the same, most of the credit of my version goes to TheDunkis.


-The Red Book of Westmarch



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    59 Discussions

    Hmm, well, that is rather simple, so let me explain. Do you see the first layer of the tube (the inner-layer that the stock goes around)? Well, build three of those (that have adaptations so that you can put them on your gun), then place all three together, one on top of the other, and place the green rods in the spaces as you see fit. Simple. =D I know this description is kinda hard to understand, but the concept is really simple. =D


    4 years ago

    The iar version of this is probably the best looking gun in the site in my opinion. I particularly like the beta mag

    5 replies

    Really!?!? Thanks man! I never thought I'd here that! Again, thanks man. I personally prefer the SBR version over the IAR, but that is just me. =D

    Sure, I can understand that. =D I kinda liked the G3 version, but it was too long and heavy for my tastes. Thanks again! BTW, you should get a profile pic.