About: I make K'nex guns, specializing in semi-automatic, RBG-Slingshot hybrid systems which i use in most of my guns. Note: I am not responsible in any way for any damage, injury, or death caused by my Instructab...

This is my Masterdude Heavy Machine Gun (MHMG). It is made for power and shooting a lot of ammo in not a lot of time. It shoots the same ammo as my MBSR and has a hi-cap magazine. It also has a large bi-pod and can have a strap.

-Strap compatible
-Trigger guard
-Large ammo
-Hi-cap magazine

-Uses too many pieces for some

More Instructables by me.

Image 1: View of gun with bi-pod.
Image 2: View of gun with strap.

Teacher Notes

Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.

Step 1: Main Body: Making the Components

Make the following. Due to the large amount of parts each part will be assigned a letter:

Image 1-2: Make 3 of each. (Parts A & B)
Image 3: Make 2. (Parts C)
Image 4: Make 1. (Part D)
Image 5: Make 2. (Parts E)
Image 6-8: Make 1 of each. (Parts F, G, & H)
Image 9-10: Make 2 of each. (Parts I & J)

Step 2: Main Body: Construction

Follow the images:

Image 1: Add a blue rod to Part C.
Image 2: Add a blue spacer.
Image 3: Place Part J but don't connect, blue spacer, and blue rods.
Image 4: Add Parts A, B, E, and F and white rods.
Image 5: Add Parts A, B, F, H, I
Image 6: Add Parts A, B, E, and F and a blue spacer.
Image 7: Place Part J and a blue spacer as shown.
Image 8: Add Parts C and G, metallic blue and tan clips where shown.
Image 9: Add metallic blue clips and blue rods where indicated.

Step 3: Bi-Pod

Follow the images:

Image 1: Make 2 of these.
Image 2-3: Make 2 of these.
Image 4: Attach the earlier made parts as shown to make 2 of these.
Image 5: Add white rods to a white connector as shown.
Image 6: Add parts to make this.
Image 7: Cover with a white rod.
Image 8-9: Add red connectors where shown on both sides.
Image 10: Connect the legs to the main bi-pod hinge.
Image 11: Connect to gun's barrel as shown.

Step 4: Strap

When adding a strap, attach the strap where indicated.

Step 5: Loading and Firing

To load, take the blue rods at the ammo feed off and hook the rubber-band at the end of the barrel and the spokes at the back as shown in the images below. Then place the blue rods back into place and then load the magazine as shown with the ammo shown. Add the ammo pusher made in the gun component step as Part D.

Image 1: Standard ammo.
Image 2: Armour piercing ammo. White rod at tip can be sharpened but I advise against it.
Image 3: Mag loaded.
Image 4: Rubber bands hooked on tip of barrel.
Image 5: View of ammo feed when loaded.
Image 6: View of spoke when loaded.

Warning- This may cause harm or injury if misused. Do not point it at people. I am not responsible for damage, injury, or death caused by this instructable.

Be the First to Share


    • Book Character Costume Challenge

      Book Character Costume Challenge
    • Made with Math Contest

      Made with Math Contest
    • Cardboard Speed Challenge

      Cardboard Speed Challenge

    35 Discussions


    8 years ago on Introduction

    Very good gun, looks creative and very good.
    Also, I'm gonna buy more knex but all I have to spent is £20.
    Where would you reccommend buying knex?
    The actual knex store (, Amazon or any other sites (I don't trus Ebay.

    6 replies

    Reply 8 years ago on Introduction

    google knex user group, they sell every knex piece ever made for really cheap. i got about 500 pieces for less than £10


    Reply 8 years ago on Introduction

    I have already checked out knex user group and they do have a few good deals/offers, I don't think i'm gonna buy any.
    I'm quitting K'Nex and moving onto modding NERF guns/blasters.

    I find garage/yard sales to be a good source but I don't know if you would be able to find any near you. I myself also don't trust Ebay but Amazon could be a good choice. I'd choose a tub of K'nex, not a set, and not one with those K'nex bricks because they are useless (well atleast for me).

    You really do think like me, but I don't know anyone in the area that I live in that does garage/yard sales.
    I don't find the bricks useful either.
    I will try Amazon and try to find the best deal.

    MasterdudeMr. Muggle

    Reply 9 years ago on Introduction

    Well, it's my version of a machine gun. I tried to add a motor to it to make it full auto in a way but the motors I have are too weak and even when I modded it to 6 batteries from 2 it was to slow to be practical.

    If a machine gun is fully automatic, then no, however if it's a gun which can obtain a high rounds per minute and has a large ammo capacity, then yes.