The S4 - a New Type of Bolt Action

About: I used to build K'nex guns. I'd like to think I've grown to be quite good at it, however, I've lost most of my interest in K'nex over my first couple of years in High School, but I do occasionally still come...

hey guys ! i've finally gotten round to perfecting my S4. it's been lying around for a long time now, having quite a few problems that i wasn't sure how to fix. i had an idea for one of the problems, but that would mean completely remaking the whole receiver area, which is by far the most complicated part, and it would probably lead to other problems as well that i had already fixed before. so i was lazy about doing it and i didn't have all that much time anyway, but i've recently had a lot of time, and i used it to try to see if there is a simpler solution for my problems (i just know you can insert some sort of joke over here, but i won't). the biggest problem was that it didn't always load so smoothly, and would often jam while loading, which wasn't an option. a few other problems included:
it was hard to load because there was a lot of friction on the loading plate.
the magazine was quite hard to insert.
the trigger was giving me a lot of problems.
i found a solution for all of those problems, and i am now very happy with the gun. as promised (it took a little longer than i expected, but it's here now), it's posted. now go build it.

sorry for the blur in some of the pictures, it just takes too long to upload the pics from a normal camera, so i use my ipod instead, which is about 1/10 of the size. you can still manage quite well.

remember to check out my slideshow 'ible here.

don't forget to RATE, COMMENT and SUBSCRIBE !!! for more awesomeness.

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Step 1: BALLS !

i'm just gonna leave this step empty because of the horrific new display that requires you to see all the pictures at once, making it very annoying to go down to the comments. also, a quick reminder to read EVERY image note.

Step 2: The Gun

in this step you will build the entire gun. have fun lol.

Step 3: The Magazine

make yourself a magazine or a few so you can actually use the gun. my magazine can hold 15 rounds. if you make a bigger or smaller magazine, just know that each connector you add or take off is worth 6 bullets. so if, for example, you make the mag 1 connector shorter, it will have a capacity of 9 rounds.

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    37 Discussions

    Hey bro!

    Nice job! I really enjoy the looks of the gun, and it seems to be a nice concept! I am not quite sure how your bolt action guns work, but after watching your videos, they seem to work well for you. I am not a big fan of the angle of the handle, I find guns that have handles like that somewhat uncomfortable...but that's just my opinion. Why don't you go take a look at my three Magpul PDR 'ibles (there's a video, a teaser, and an 'ible!). Would you also tell me how you think I could improve the video, if you have any comments on that.

    3 replies

    Just reviewing some old comments on one of my own favorite guns... I guess now you do understand the BA concept, after having built the ZKAR... See how difficult and innovative this gun is? It took me a long time to get right though, I'll tell you that much.


    6 years ago on Introduction

    I just built it. It is amazing but sometimes when I push the bolt forward, it gets stuck halfway. Can you help? Also, i am getting both trigger problems. The ram snaps forward when I am pushing the ram forward, andI cant pull the trigger sometimes. Should I send pics to help?

    4 replies

    Reply 6 years ago on Introduction

    I wouldn't really know about any of those problems, I never got them. Try seeing if you did the bolt panel correctly and the trigger maybe as well. Another thing you could try is changing the rubber band ratios between the ram band(s) and the trigger band(s). Try using weaker rubber bands on the trigger and if that doesn't help, try doing the same for the ram. If all else fails, if you'd like, try to rebuild the gun.


    6 years ago on Introduction

    Thanks. I fixed those but now when the bullet is pushed forward, it goes so far into the chamber that the ram can't hit it. Sometimes the bullet falls into the trigger guard area

    Sharir1701Inventor X

    Reply 6 years ago on Introduction

    very sturdy. the gun doesn't wobble much, not without intentional pressure. the cheek rest (the part above where the ram is with the brown connectors) is a bit bendy and easily opened up, but i did that on purpose for comfort (a bendy, in other words, adjustable, cheek rest is very comfortable imo) and for ease of ram band replacement (you have to open it up to replace the bands, and i don't want that to be too complicated). i wouldn't drop it on solid ground from a floor though, but then again, you could say that about almost all guns. i've never had any problems with it's sturdiness, anyway, and it never affects the extreme accuracy of the gun. i hope this helps.