Jonaboy's Semi-auto Knex RBG gun

Picture of Jonaboy's Semi-auto Knex RBG gun
This is the result of my attempt to make an "inexpensive" (uses few parts) semi-auto knex rbg. (rubberband gun) I got kind of tired of finding Knex rbg guns that are great but take a gazillion parts to make. In addition, it doesn't look too bad, either, being somewhat reminiscent of an M1A3 "Grease gun". You are welcome to offer ideas and/or constructive criticism. Please let me know how you like it. :D
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Step 1: Photo of parts needed.

Picture of Photo of parts needed.
Honestly, I don't think I really need to list out all of the parts. A picture's worth a thousand words anyway. :P

Step 2: Making the handle/ grip

Picture of Making the handle/ grip
No description really needed, I think.

Step 3: Now, the barrel...

Picture of Now, the barrel...
Six "grey" spacers, (or 18 blue ones, six to a side) 3 to a rod, and four black y connectors. Note: The connectors (the y ones...) don't have to be y connectors, they can be just about any other connector you have on hand that'll fit... however, I find the y ones to be the best.

Step 4: Then, you build...

Picture of Then, you build...
This green and yellow bit, which gives structural support to the barrel, and keeps the end part of the barrel (the purple and blue piece, w/ the yellow piece and rod) from sliding towards the trigger due to the force of the rubber band on the barrel (end). Attach the blue and purple bit to the two grey rods of the barrel, and connect the two green and the one yellow rods to the purple connector already on the two grey rods. (hereafter referred to as the barrel).

Step 5: Attaching the Handle to the barrel

Picture of Attaching the Handle to the barrel
Now, you're going to make the handgrip that goes on the barrel. Just follow the pictures.... BTW, the deconstruction of the barrel support is to make it easier to put the yellow connector piece on the barrel...
Wafflicious5 years ago
Um... It's single shot I think not semi auto =)
jonaboy110 (author)  Wafflicious5 years ago
Well, sort of. It's actually (because of the spring that resets the trigger) semi-semi-auto, but that doesn't sound very good, (or smart... o_0) and I doubt anyone would be searching for a "semi-semi-auto RBG gun". xD Thanks for commenting anyway, though.
actually it's single shot.. You reload the ammo after every shot.
jonaboy110 (author)  Wafflicious5 years ago
No, it's semi-semi auto... you have to reload, but you don't have to reposition the trigger, like you do for most (all?) of the other Knex RBGs of this type....but whatever. I'm not going to quibble over the term. (much...) -_- It's close to being semi-auto, and to me that's about all that matters.
Nooo If you have to reload it's not
the trigger doesnt reset on my gun :/
jonaboy110 (author)  HaylingZar1 year ago
Please look at "Step 8", and be sure you have the trigger spring installed correctly.

About operating the trigger: When you've pulled on the trigger, the yellow connector that's parallel to the barrel should come down about 90 degrees, so just slip your fingers out of the area of the trigger, and ahead of the flat space of that same yellow connector. Pull back, like you're trying to get the trigger to go further back, and then let go. (Eg slide your fingers off the side of yellow connectors) It *should* snap back and "click" back into place. :) :D

Thanks for building, and commenting.
semi-semi-auto is a single shot. semi-auto is where it shoots once every time the trigger is pulled. semi-semi-auto would be where you have to reload every shoot. a trigger resetter is the oldest thing ever made for knex guns, and it is nothing new, and most if not all knex RBGs have them.
Thanks that's a good way to put it.
thx dude its great
i realy like this coz i havent got a lot of pieses and this is a realy good gun thanks :)
KnEx_MaStEr3 years ago only put the conectors in the instructions no rods never taught us to fire it good range i rated it 3.5
jonaboy110 (author)  KnEx_MaStEr3 years ago
First of all.... thanks for commenting. :) Just sort of FYI, and to everyone else reading this too, I'm not sure if I mentioned it or not in the instructable, but the green rubber bands that they use at Whole Foods, for containing cartons of berries, and salad boxes, etc., really work best as far as range. I have absolutely no idea what size they are, but if anyone has any idea please let me know. I'm pretty sure I put the rods too. If you mean the original photo, showing all the parts needed, the picture of the rods is the second one over... you have to click on it. Thanks... I'll add that now.
sorry u did include the rods p.s good gun
jonaboy110 (author)  KnEx_MaStEr3 years ago
No problem. :D Actually I'm just glad that someone commented... and, thanks for the compliment. :)
your welcome i subscribed
jonaboy110 (author)  KnEx_MaStEr3 years ago
Yeah I noticed.. thanks. :)
your welcome
wow i didnt think it was posibale but u acctually pulled it off... a rbg that isnt semi auto!!!! ALL RBGS ON THE SITE ARE SEMI AUTO!!!!!!!! omg .5 star....
I made a rbg that wasn't semi-auto... didn't post.
jonaboy110 (author)  Ltcheesecracker5 years ago
how does the rubber band go on i cant see it and how does it fire and how do i load it 5stars+
jonaboy110 (author)  yourworstnightmare3 years ago
 Uh, if you look at the completed gun ( the end product, as it were) you should see an orange (horizontal, rectangle looking connector, but they're normally just called "orange" connectors) connector. You hook the rubber band through the end (open end of the "h" of the connector) and stretch the rubber band (be careful that it doesn't come off of the orange connector as you do so) over, onto the green peg, (Uh, that one's typically just called a "green rod") on top of the white circle connector trigger assembly. You can see it in 2 of these photos here, just sticking out over the trigger assembly's yellow half-circle connectors. 

Hope that wasn't too confusing, and helped. Thanks for the 5 stars. :)

lewismarsh4 years ago
does it fire and if so how?
yerjoking5 years ago
I hear you say that the trigger resets. Every RBG trigger resets it's self, if it was semi auto, that is. This is not semi auto, nor semi-semi auto. But it is cool.
pls5 years ago
You only need to have the gun on the intro picture O.o
jonaboy110 (author)  pls5 years ago
Yeah, I know. I didn't purposefully put that there, it did that on it's own. o_0 I don't want to accidentally delete all of the "real" steps, so I'm not going to mess around with it now.. soz about that. BTW, your instructables pwn. B) Esp. the gatling gun.... #_# (dead guy...)
ya, if you upload all the pictures on the intro they get put there. all you need to do so this does not happen on future instructables, is only upload the pictures you need for each step, and then upload the pictures needed for the step when you get to it.
jonaboy110 (author)  dsman1952765 years ago
Oh, ok, cool. Thanks :)
pls jonaboy1105 years ago
Oh okay, don't worry about it then, better be safe than sorry! And thanks for the compliment:)

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