Introduction: Under Barrel Grenade Launcher for the MAR

Picture of Under Barrel Grenade Launcher for the MAR

This is an Instructable for an under-barrel grenade launcher for my MAR. It launches grenades which throw fragments around the area of impact upon impact.

Note: The grenade launcher has a block trigger but since this is more of a secondary, special, or back-up weapon I guess it doesn't matter as much.

More Instructables by me.

Step 1: Making the Components

Picture of Making the Components

Make the following:

Picture 1: Make 2 (Lets for now call these part A).
Picture 2: Make 1 (Lets call this part B).
Picture 3: Make 1 (Lets call this part C).
Picture 4: Make 1.
Picture 5: Make 1.

Step 2: Construction

Picture of Construction

Follow the images:

Picture 1-2: Add "Y" clips where shown (there should be 8 of them).
Picture 3-4: Add the earlier made parts where shown.
Picture 5: Place white rods where shown.
Picture 6: Add the earlier made ram rod and add rubber band(s).

Step 3: Ammo

Picture of Ammo

These are different types of ammo which can be used. These can be hard to make. I suggest first putting the spacers on the rod and putting the "Y" clips at the ends and using you fingernails or something thin to push the rod so both "Y" clips hold on. Then add the gray or metallic blue connector.

Step 4: Placing, Loading, and Firing

Picture of Placing, Loading, and Firing

Lock the white rods so they connect into the grip as shown in image 1. Place the rubber band like in the 2nd image. Pull the ram rod back as in image 3 until the trigger blocks the rod from pushing the ammo out and place the ammo in the barrel. Push the trigger to the side to fire (Its a block trigger).

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.


aleceatsfood (author)2010-12-15


Masterdude (author)aleceatsfood2010-12-16


aleceatsfood (author)2011-02-20

here it is, its on a crossbow and the 3rd pic is of shotgun ammo the 4th pic os of grenade ammo! thanks it cool. I have to add more to the cross bow to make it stay stedy but here...

Masterdude (author)aleceatsfood2011-02-21


aleceatsfood (author)Masterdude2011-02-21


Fred the evil puppet (author)2010-07-26

why did i make this and it never worked?

What do you mean that "it" never worked? Did the grenade not shoot out? Did it not fragmentate? Did the trigger not want to move? Or something else? The design is so simple it should almost never fail totally.

it was the gun itself. sorry, i meant to say the gun. it just never fired. i know i built it 100% correct.

Why didn't it fire? Did you use rubberbands or did it just jam constantly?

it jammed

Maybe the ram rod when the trigger is pushed aside hit the white connector? In this case you just push it up until it goes through the hole in the white connector.

ah. thanks. now it shoots!

You're welcome.

Fred the evil puppet (author)2010-07-28

it jammed.

GAG3 (author)2010-04-15


Masterdude (author)GAG32010-04-15


GAG3 (author)Masterdude2010-04-15

M bar?

Masterdude (author)GAG32010-04-16

Are you just referring to my guns or are you trying to make a joke? If it is supposed to be a joke, how about explaining it or using more words so it can be understood?

GAG3 (author)Masterdude2010-04-16

Referring to YOUR guns

Masterdude (author)GAG32010-04-17


GAG3 (author)Masterdude2010-04-17

I built it...IT'S AWESOME...Thank's dude.:)

Masterdude (author)GAG32010-04-19

Hey, I'm going to post a new gun soon. It's the MHMG. It has a hi-cap mag, bi-pod, and can have straps as shown. Here's a preview of it:

Mr. Muggle (author)2009-12-09

I was the first one to build a MAR:

DJ Radio (author)2009-12-07

These kinds of "Grenade launchers" are just another excuse to post lame block triggers.  

Masterdude (author)DJ Radio2009-12-08

I do admit that block triggers aren't really good and that true triggers are a lot better but to make a working grenade launcher small enough to fit under the barrel and look more-less realistic I had to use a block trigger.

magnierk (author)DJ Radio2009-12-08

 you're lame

DJ Radio (author)magnierk2009-12-08

Who cares?  I'm still right.

~KGB~ (author)2009-12-08

cool ammo!

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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