Introduction: MSMG

Picture of MSMG

This is my MSMG (Masterdude Sub-Machine Gun). It has a true trigger and like most of my guns is semi-auto (there is some controversy over the term semi-auto but according to me in K'nex it means that every time you pull the trigger, a shot is fired)

-Removable magazine
-Adjustable stock
-Rather easy to use
-Adjustable cheek rest (when stock is extended you can slide it where you like it)
-True trigger

-Handle might be uncomfortable for some people
-Can be hard to load at first (But becomes easier with some practice)

Image 1: Stock extended.
Image 2: Stock compacted.

More Instructables by me.

Step 1: Main Body: Making the Components

Picture of Main Body: Making the Components

Make the following. Each will be assigned a letter for identification:

Image 1: Make 1. (Part A)
Image 2: Make 1. (Part B)
Image 3: Make 2. (Part C)
Image 4: Make 1. (Part D)
Image 5: Make 1. (Part E)
Image 6: Make 1. (Part F)
Image 7: Make 1. (Part G)
Image 8: Make 1. (Part H)
Image 9: Make 1. (Part I)
Image 10: Make 1. (Part J)
Image 11: Make 1. (Part K)

Step 2: Main Body: Construction

Picture of Main Body: Construction

Follow the images:

Image 1: Add white and blue rods to part A where indicated.
Image 2: Attach part B and add white and blue rods.
Image 3: Attach part C,  white rods, and 2 blue spacers.
Image 4: Add parts D, E, F, G, and H.
Image 5: Add part C, blue spacers.
Image 6: Add part I.
Image 7: Add parts J and K, and tan clips.
Image 8: Add metallic blue clips.

Step 3: Stock: Making the Components

Picture of Stock: Making the Components

Make the following. Each will be assigned a letter for identification:

Components A: Follow images 1-3 to make this component. Make 4 of these.

Component B: Follow images 4-6 to make this component. Make 1 of these.

Component C:  -Image 7: Make 2.
                             -Image 8: Make 3.
                             -Image 9: Add blue rods.
                             -Image 10: Add 3 parts as shown.
                             -Image 11: Add the last part.

Step 4: Stock: Construction

Picture of Stock: Construction

Follow the images:

Image 1: Take 2 of the earlier made parts and add 7 orange connectors.
Image 2: Take earlier made parts and connect as shown.
Image 3: Add 5 orange connectors and connect as shown.
Image 4: Connect another of the earlier made parts as shown.
Image 5: Attach all those parts as shown.

Step 5: Magazine: Making the Components

Picture of Magazine: Making the Components

Make the following:

Image 1: Make 2.
Image 2: Make 1.
Image 3: Make 1.
Image 4: Make 1.
Image 5: Make 1.

Step 6: Magazine: Construction

Picture of Magazine: Construction

Follow the images:

Image 1: Add white rods.
Image 2: Place the earlier made parts as shown.
Image 3: Cover with the earlier made part.
Image 4-5: Finished magazine with ammo and pin in place.
Image 6: Ammo.

Step 7: Putting Everything Together

Picture of Putting Everything Together

Connect the parts you have made as shown.

Step 8: Loading and Firing

Picture of Loading and Firing

This gun loads and fires like most of my guns like my MAR, MAR-2, MSAU, ETC. To load you first remove the magazine and put the pin in place, and then you insert the ammo which is shown in the image below. Then you insert the magazine into the appropriate place until it firmly holds in place. They you push the white rods over the ammo feed out to the side and you take the rubber-bands and hook them on the tip of the barrel and then on the spoke in the back of the gun. Then you push the white rods back into place and pull the pin out of the magazine. To shoot you pull the trigger.

Image 1: Ammo.
Image 2: Loaded. View of barrel end.
Image 3: Loaded. View of ammo feed.
Image 4: Loaded. View of trigger system.
Image 5: Magazine in place. Pin in.
Image 6: Magazine in place. Pin out.
Image 7: First person's view.

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.


~KnexBuild~ (author)2011-11-18

awesome adjustable stock.

Masterdude (author)~KnexBuild~2011-11-18


~KnexBuild~ (author)Masterdude2011-11-18

no problem

skyfaller (author)2011-07-25

Awesome! 5 stars.

Masterdude (author)skyfaller2011-07-26


~KGB~ (author)2010-03-31

wow! 5* pretty cool!

Jedi_man (author)2016-06-13

I built it, but unfortunately it didn't work for me. I'm sure it's a great gun when it works though!

I decided to make a parts list while disassembling it.

-----Rods: 234-----

Green: 146

White: 64

Blue: 19

Red: 5

-----Connectors: 210-----

Grey: 55

Light Grey 2-Way: 5

Orange: 25

Red: 17

Green: 17

Yellow: 79

White: 6

Blue 3-D: 6

-----Misc: 26-----

Y Connector: 8

Tan Connector: 3

Metallic Blue Connector: 4

Male Ball Joint Connector: 1

Black Hinge: 2

Blue Hinge: 2

Blue Spacer: 6

-----Total: 470-----

You're welcome :)

Champsquire (author)2013-05-14

Well, i finally finished it, and it took up 75% of my pieces, not to mention it looks different in some spots, but i love it, and it is Semi auto, if you hook up 4 bands to it, and put them on every other spike on the wheel, it will shoot 4 rounds. (i know this because of a gun i had built a while ago, and this has the same mechanism.

Fred the evil puppet (author)2012-10-30

i still think this is one of your best guns.

Thanks. I'm coming out with a new full auto version of this soon. Made a breakthrough with full auto and am making some full auto versions of some of my previous guns along with some new tweaks I've found to be helpful since the originals.

wow. thats amazing, im really looking forward to a full auto compact smg.
would it only have 8 shots though, or multiple discs?

It's already out, it's the MASMG. These guns can have more than 8 shots, you just rotate them a full turn and start doubling up the bands.

djputa333 (author)2011-08-21

here's my problem, I follow everything to the letter, but I don't understand how it shoots, it need to shoot the elastic too and it doesn't shoot far...

Masterdude (author)djputa3332011-08-22

When you shoot the rubberband is probably going to shoot as well but it should hook on to the ammo. The rubberbands should also be rather tight when pulled back for maximum power.

Fred the evil puppet (author)2011-04-23

Can you use White rods as AP rounds?

No. My RBG/Slingshot Hybrid guns can only use connector based ammo. However in some of my other guns you can have some flexibility and can change the tip of the ammo.

Fred the evil puppet (author)2011-04-23

I have a (friendly) war coming up and need a good assault rifle for the job. One of my friends doesn't have any Knex and I need to make his gun for him. So I need a low peices, efficient and reliable Knex assault rifle. Should I built this or the MSAU 1/2, or perhaps the MAR?

I would recommend the MSAU (both have their pro's and con's) and the MAR's/MBAR's. The MAR's/MBAR's use more pieces than the MSAU's, but the ammo is larger so more power and they have better features like sights, grenade launchers, etc.

SomeAsianKid (author)2011-04-11

piece count please :D

Masterdude (author)SomeAsianKid2011-04-11

Sorry but I probably will not make one (Meaning: No).

Seleziona (author)2010-04-11

I like, but one problem: the stock uses way too many grey connectors, and the ammo is grey connectors.... 4.5* anyway

Masterdude (author)Seleziona2010-04-12

So you mean that because the ammo is gray connectors, it isn't the best because it uses a lot of them. I think there shouldn't be problems such as using up all you gray connectors if you have enough parts. Most people should have enough gray connectors for both the gun and ammo.

tubanator-2.0 (author)Masterdude2010-05-07

im pretty sure id be in seleziona's prediciment with not having enough gray connectors.but thats an easy fix by modding the stock also 5*

Seleziona (author)Masterdude2010-04-12

I hardly have any grey cons.... I don't even have many orange connectors. That's why I don't build your guns. They use connectors for ammo :(

Masterdude (author)Seleziona2010-04-12

Well.... that could be a problem. I see based on your instructables that you do have an OK amount of K'nex, just not the parts needed. I suggest going to garage sales to get lots of K'nex and maybe modding guns so they use less of the parts you don't have.

Seleziona (author)Masterdude2010-04-12

Ya man, I got a good amount of knex, I just don't make huge things. 
1: I always am at garage sales in the Summer (at least half of my knex is from garage sales)
2: I always mod people's guns so It can use less parts.
Thanks for the advice anyway!

Oh ya, the only really big thing I've ever made is my perfect war gun. (look at my forum topics)

182515 (author)Seleziona2010-05-05

I think that i saw somewhere that you live in canada so try I just doubled the amount of knex i had from buying it from Kjiji ( it was $50 but would have cost 50-100 dollars on ebay.)

Seleziona (author)1825152010-05-06

hmmm. never heard of that site!

Masterdude (author)Seleziona2010-04-12

I actually got all of my K'nex from garage sales. It's an OK amount but I'm still trying to find more (the more the better!).

Seleziona (author)Masterdude2010-04-12

Cool :D

knexguy (author)2010-03-31

Good gun, but it is generally accepted that 'true triggers' are triggers that are pulled straight back in a realistic way; what you mean is 'semi-automatic', this is when every time you pull the trigger a shot is fired without having to cock the weapon inbetween shots.  However, this mechanism here is considered 'pseudo-semi auto', or my personal favourite 'quasi-semi auto', although I just thought that up now and no one really uses that.

I hope I didn't confuse you too much.

Masterdude (author)knexguy2010-04-01

Yes, I understand the 'semi-automatic' dilemma, but I just simply consider it a 'semi-auto' because a shot is fired for every trigger pull without cocking it between shots, regardless of whether or not you have to put on lots of rubberbands as in this system. A couple people have told me what you tell me but these are K'nex guns, not actual guns so the terms have to be configured accordingly to the situation and I think it is all right in calling these guns semi-auto.

knexguy (author)Masterdude2010-04-02

Obviously I did confuse you...

I have no problem with it either, but you wrote that a true trigger means it fires every time you pull the trigger.

'It has a true trigger and like most of my guns is true trigger (there is some controversy over the term true trigger but according to me in K'nex it means that every time you pull the trigger, a shot is fired)'

Masterdude (author)knexguy2010-04-02

I fixed it.

Oblivitus (author)Masterdude2010-04-01

There's no doubt about it in my mind. It's semi-auto.

Millawi Legend (author)2010-04-02

Sweet! When i first saw it i thought it used my mech and was full auto but when i looked closer thats just the stock. Very nice 5*.

Vynash (author)2010-03-31

Nice!!! 5*s

About This Instructable




Bio: 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 ... More »
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