K'NEX Gun: Reliable (R3) (Build)

K'NEX gun builder here at Instructables. More or less retired from the community, but I still pop...

The RMACR, posted on Mar 9, 2013, has always been one of my favorite builds. Efficient, yet simple, the Reliable (A.K.A. R4 / RMACR V.2) is a great indoor K'NEX War gun. After firing at least 100 rounds through it, I have yet to experience in using it. Getting ranges of up to (if not over) 50 ft. and being simple enough to mod into any shape, the Reliable is just that, reliable.

My reason for rebuilding this gun was simple, I wanted to revisit some of my "older" builds. Although this is the same mechanism as my RMACR, it has multiple changes from the first version. This version is longer, the sights are much better, the stock is stronger, the handle / grip is more comfortable, the attachments bars are new, and the trigger guard is cleaner.

- 16 rd. magazine
- Long pin pull
- Nice sights
- Great stock
- Sturdy magazine
- New attachment bars
- Comfortable grip / handle

Without further adieu, lets move on to step #1...

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Step 1: Right Panel

In this, the first step, you will be building the right-hand panel. Note the blue rods and the white rods placed perpendicularly, as well as the grey gear in picture #3. Also, keep the image notes in mind. And, as always, if you need help, just ask. Once you finish this step, move onto step #2.

Step 2: Internals

In this step you will be working on the internals of the Reliable. You will see one or two broken pieces, but, if you check the image notes, few of them should be necessary. Again, the image notes should guide you through the tougher pictures, and if you need help, just ask. Once you are done with this step, move on to step #3.

Step 3: Handle / Grip

Now we are going to work on the handle / grip. This is a good place to start modding the Reliable. Go ahead and, as long as you keep the same connection system (the way the handle connects to the gun), make the handle to your preferences. Once you are done following the pics and modding your handle, move on to step #4. This step may not be as much in detail as some of the others, but since I hope you mod this handle to your preferences, you should not have any problems. If you do, however, drop me a note.

Step 4: Trigger Guard

This step is relatively easy. You now have the choice of building the trigger guard, modding it, or just going with out it. If you chose to go without it, read all the image notes to make sure you do what you need to. Move on to step #5.

Step 5: Left Panel

Now, build the left-hand panel,and place it as you see in the pics. This step is just as easy as step #4, so you should not have any questions, but, if you do, drop me a note. Once done, move on to step #6.

Step 6: Stock

In this step you will be building the stock. It should be easy to build, but this is another place where you could mod the Reliable. Change the stock to to fit your preferences. I built it this way, you can build it a different way. Again, if you have questions, I am here to help. As always, once you are done, move on to step #7.

Step 7: Sights

The sights are also another way that you could mod the Reliable. Make them the way you want them. Also, keep the image notes in mind, as they will help you. Again, if you want help, just ask.

Step 8: Adding Some Extras

In this step, step #8, you will be putting on rubber bands and lots of other extras including gears and side-panels. It should all be relatively easy, but if not, let me know. Once you are done, we will move on to step #9.

Step 9: The Magazine

Here are just some pictures of the magazine. And yes, to answer your question, the broken rods are necessary. You can make the mag shorter, longer, straight, or bent in the opposite direction if you want. This might be one of the harder steps, so don't feel afraid to ask questions. Move on to step #10.

Step 10: Finishing Up

This is the last step on how to build the Reliable. Essentially what you will be doing in this step is adding bands to the gun. You can use what ever bands work best for you, or what ever bands you have around the house, but in this step, I am using 3 size #64's.

Now that you are done, go and shoot the dad-gum thing.


-The Red Book of Westmarch



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    77 Discussions


    Reply 6 months ago

    Do you know how to stop the trigger from getting stuck, could you help


    1 year ago

    dude chilllllllll. their really good and they fire well.


    1 year ago

    Cool! Will build! Looks good!

    I thought somebody might say that, and I realize you and BM are real-life friends, but I do disagree, so I will show you why you are in the wrong.

    First off, the main body. This is by far the closest resemblance between the two. But, because I did not copy his body (I built it out of my mind), it is just a coincidence. I, again, can see the resemblance, but because my body is like his, and his body is (arguably) a shorted edited version of my ISSC MKII RR (although he did not directly copy it either), your argument falls to the ground.

    Secondly, the stock. All mine, not adapted from his, I imagined it and built it all (again) out of my mind.

    Anything else? My mechanism is different, my main body is different, my stock is different, my pistol grip is different, my mag is different, my fake barrel is commonplace with a ton of other peoples fake barrels (nobody can claim that they invented it), my back sight is different (my front sight is the same as BM's, his front sight is awesome)... The list goes on...

    You really should be more discerning when it comes to K'NEX guns. =D

    DSC00207.JPGBM SIG552.jpg

    well you can say what you want to say but in my opinion it looks very similar to bm. and the things that you said in the last comment is miner things.

    If that is the way you want to look at it, fine. I just think that if I had e different stock, you would not have said the same thing. All the same, to each his own.

    The pistol grip is what you might call the handle. I usually call it the pistol grip as that is the precise name for it. Got any K'NEX projects coming up?

    im making a safe it not to special but im still going to post it.and after that i think after i might a v2 to my knex wheeler launcher. check it out if you dont know what it is.

    wezils tuts

    4 years ago on Introduction

    I just built this gun and it is amazing! The only issue that I am having is when I pull the trigger, the mech just gets stuck in pulled position. I added rubber bands like they were in the pics but that isn't the issue. How can I fix this?


    4 years ago on Introduction

    Ah, one of the first good knex guns I built. It works very smoothly and shoots well.


    5 years ago

    i usually make pistols (just made your five seven and I love it) I plan on building this in a couple days it looks awesome so I hope its worth the pieces!