Introduction: Full/Semi Auto Oodammo Slingshot

Picture of Full/Semi Auto Oodammo Slingshot

I don't have the entire gun made with real knex, but I did build the trigger to ensure that it works. It has a 3 round magazine (you should be able to use up to 5 rounds with a little less range per shot) and fires the bullets consecutively as the trigger is pulled down (you can fire full or semi auto this way). Add elastics to the trigger, attach 3 elastics (one for each round in your guns max capacity) to each of the blocks (6 elastics in all) at the front tip of the barrel.

If you build this, please take picture(s) and/or make a video.


heatblast (author)2010-04-14


KnexFreek (author)heatblast2010-04-24

 the hellslayer is a pretty dam innovative oodammo gun, go check it out!

Oblivitus (author)heatblast2010-04-22

I just made a version 2. Check it out.

slipdiddy101 (author)2010-06-26

looks awesome... have you built it? and if you have, whats its range?

Eddiepers (author)2010-04-18

Can i have the .ldr file for that gun, i really want to build it


u can email it to me


Oblivitus (author)Eddiepers2010-04-18

I just sent the file.

Tom Buckey (author)2010-03-29

Made it and its amazing!!!!! I'll post a video soon. but one problem.. I've been testing and making a few mod's and havent yet song it semi-atuo. But overall an great gun no faults very comfy, havent tested the range yet but will soon.

Oblivitus (author)Tom Buckey2010-03-29

Cool, thanks. What did you mean by "havent yet song it semi-atuo"? Can you elaborate please?

Tom Buckey (author)Oblivitus2010-03-29

I was ment ot say " haven't yet SHOT it in semi-auto" It's quite difficult.

Anyway here is a video:
I only just uploaded it so it might not work yet.

Oblivitus (author)Tom Buckey2010-03-31

Okay, thanks for the video.

Tom Buckey (author)Oblivitus2010-04-12

New, and impoved, video

Kinetic (author)2010-04-10

 Good idea, however you think it would be possible to use a sort of hinged wheel mech (i can explain if you dont know what i mean) to optimize efficiency and capacity?

Oblivitus (author)Kinetic2010-04-10

Thanks. Please explain your idea.

heatblast (author)2010-04-01

I think this might actually be good for wars :)

Oblivitus (author)heatblast2010-04-02

It depends on whether or not the trigger can be pulled slowly and easily enough to fire semi auto. Take a look at tombuckey's video link on this page.

maybe arachet type mech that makes it click into place after it fired the oodammo

heatblast (author)Oblivitus2010-04-02

You got a point there, I'll give you that. But sometimes repeaters aren't always reliable. On some occasions they are, other times they're not. I guess it just depends on what type of gun you have, and whether you're confident that it's really accurate or not.

Millawi Legend (author)2010-04-01

Your really good a MLCad. I'm just starting out. I made a TR8 in it and it turned out pretty well.

Oblivitus (author)Millawi Legend2010-04-01

It's pretty good. You can custom select colors to be more realistic and then duplicate the piece to make all of those pieces match.

Millawi Legend (author)Oblivitus2010-04-02

Can you? Cool i'll have to give that a go.

Mr. Muggle (author)2010-03-28

 Ah, finally, I've stared 5 minutes at my computer screen and now I get it! good idea!

It took you five minutes to understand this simple mechinism.

lol, not sure how long exactly, but I was only watching the first pic =D

Oblivitus (author)Mr. Muggle2010-03-28

Lol, thanks.

builder968 (author)2010-03-28

Good idea!

KnexFreek (author)2010-03-25

Brilliant! I have had many ideas like this, but i was to lazy to build! If i build, can i post? I will give you the credit. :) 5 stars and a fave.

Oblivitus (author)KnexFreek2010-03-25

Thank you. Like I said in the intro, I didn't really build this either, just designed it on mlcad. And in response to you posting it; yes, absolutely, I'd love it if you'd post it, it saves me a lot of work. XD

KnexFreek (author)Oblivitus2010-03-25

 Ok i will post this week, or wait... its the end of the week. Expect it done by friday!

Oblivitus (author)KnexFreek2010-03-28

It's Sunday, how's it coming?

KnexFreek (author)Oblivitus2010-03-28

 what do you mean? I said expect it done by friday... as in expect it done by next friday. LOL sorry for the confusion :) 

Oblivitus (author)KnexFreek2010-03-28

Ahh, okay.

Oblivitus (author)KnexFreek2010-03-26

Great. Make a video for it too.

KnexFreek (author)Oblivitus2010-03-28

 i will

Oblivitus (author)KnexFreek2010-03-28


TheDunkis (author)2010-03-27

Hmm an idea I had a long time ago is instead of having the trigger go all the way up, have it go only through the bottom piece. Then have another guide from the top so it all drops down. Then you hold the trigger and they'll keep dropping and flinging. When the trigger is up, it pushes against the other guide pole so the bullet just transfers. That would be a little more complicated but then at least you could have a larger magazine and a more precise gun. Think you could try making that after?

Oblivitus (author)TheDunkis2010-03-27

That's a good idea. I came up with another idea shortly after designing this. I was thinking that I could make the trigger push rounds off the top of the rod, that would increase accuracy as well, but not capacity.

The problems with increasing capacity, however, are that;
1: The rod would have a lot of pressure on it.
2: The barrel would have a lot of pressure on it.

TheDunkis (author)Oblivitus2010-03-27

Yeah, that's why it would be better to have some sort of cog or gear though it's harder to make them work fully auto. I had an idea for a fully automatic RBG though. Wanna hear? Maybe you could figure out how to build one. I lack the pieces or else I'd try.

Oblivitus (author)TheDunkis2010-03-28

Yeah, I want to hear.

Seleziona (author)2010-03-27

I made it the day you posted it, but didn't really like it because it couldn't handle #64s....

ant ant 33 (author)2010-03-26

 dont get how it works cud sum1 pls clearly explain to me breifly what it does, or you could post it already!

barrax (author)ant ant 332010-03-27

there is a rod going through the holes in the oodammo...

when you pull the trigger, the rod goes down, releasing the oodammo...

the oodammo is on elastics..

ant ant 33 (author)barrax2010-03-27

 OHHHHHH i get it now, thank you very much

barrax (author)ant ant 332010-03-27

thats alright mate :)

ant ant 33 (author)barrax2010-03-27

 : D

Jesus. (author)2010-03-26

Can I post???

Oblivitus (author)Jesus.2010-03-27

kNeXFreek said that he's posting it. You can if he changes his mind.

Jesus. (author)Oblivitus2010-03-27


Tom Buckey (author)2010-03-27

Cannot  wait untill this comes out! Im definatly building it.

Senior Waffleman (author)2010-03-25


Thanks. You're name just made me laugh out loud, haha.

About This Instructable




Bio: I paint, write music, and used to build knex guns. I have a Bachelor's Degree in Studio Art. - updated 5/7/2014
More by Oblivitus:Z3 Knex Gun (3-Barreled Semi-Auto Pump Action Revolver)Z3 Knex GunZ3 Knex Gun Firing Demonstration
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