new gun design! help!

[nightmare]

Hello everyone, if you have not noticed already I am new to this site and I was wondering if anyone could give me some advise.

One day my buddy came over and i showed him one of my spudguns and he was hooked instantly. Well, my buddies birthday is coming up and he is a huge halo 2 freak. So, I got the idea to make him a spudgun in the design of a halo 2 rocket launcher. But, there are a few problems, in the game the rocket launcher has 2 barrels side by side, with no gap in between. So, 2 spud guns side by side wont fit the bill because of the gap. So i thought of the idea to use 1 combustion chamber to shoot out 2 spuds at once. So, here is my question, How big will my combustion chamber need to be to put out enough force to shoot 2 spuds the same distance as a regular spud gun?

and also the design is so that the cumbustion chamber is right next to your ear, so will i have to get some ear protection for him so that he wont hurt his hearing?

here is the design i have decided on:
http://img147.imageshack.us/my.php?imag ... heraa3.png

any other ideas or avise would be greatly appretiated

[chaos]

My opinion just make it the 1 chamber because the pressure is going to go out the easiest path it can find eg: the barrel with less resistance otherwise you would have to have to identical chambers with identical ammo and identical resistance. ok yer im not much help but this could be a major design fault in your plans soz I just thought i might say something.

Chaos

[jjjd]

Try having one chamber and a way to seal one of them off, then switch when you want to shoot the other barrel

[A-98]

ive considered this many times, i think that a pneumatic would be better to have one of the barrels be a chamber, and the other the barrel, with a valve concealed in the big round parts.

[nightmare]

ive considered this many times, i think that a pneumatic would be better to have one of the barrels be a chamber, and the other the barrel, with a valve concealed in the big round parts.

The whole point of the gun is so it can shoot 2 spuds, I dont care if its one at a time or both at once. Also how would i get a trigger system that would go from the valve to the spot on my design where the trigger is?
PS thanks for the posts

[Brooner115]

ok nightmare heres wat u do make this to your specs ,so you have the combustion chamber i suggest mabye a foot of 4in. pvc than a reducer to a tee thatn out from both ends of the tee are 2 elbows that then lead to two 2in. barrels. And it should work because u have an explosion which will propel wat evers in the barrel ifits not held in or tight
A line from Chaos:
My opinion just make it the 1 chamber because the pressure is going to go out the easiest path it can find eg: the barrel with less resistance otherwise you would have to have to identical chambers with identical ammo and identical resistance.

So it will work it just wont be the samme distance each potatoe goes one will go farther than the other most of the time but hey try something new!!!

[Killjoy]

As i recal, the 2 barrels of the rocket launcher in halo each fire 105mm rockets (or close to that), so if you wanted to make it as real looking as possible, build two coaxial cannons side by side with a 2 inch (or 1.5 inch) barrel and a 4 inch chamber (cause a 4 inch diam chamber is a little over 100 mm in diameter), and then costume fabicate the rest of the parts (loader, handles, etc.) to make it look real. But i don't know your skills or experience so it might be a little advance for you (no offense). Maybe this will you some ideas though.

[medievalman]

make two seperate guns like normal, the use elbows so that the barrels are touching. i think this would work, heres a crappy paint diagram!

if you cant tell, its a view from above:

[Atlantis]

The chamber doesn't have to be a different size pipe than the barrel, just stick 2 pipes together side by side and put a bigger pipe over them for the base model.

[joannaardway]

The chamber doesn't have to be a different size pipe than the barrel, just stick 2 pipes together side by side and put a bigger pipe over them for the base model.

That's what I would have said. However, you'll still have slight problems with the endcap on the chamber.

But it's probably the easiest and best way to do it.

[nightmare]

Thanks for the advise guys (and gals). im going to start the project this weekend and hopfully get pictures up the following week.
by all means, dont stop posting your ideas
thanks again
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Also, what do you guys think as far as fuel? Propane???
im looking for something that gives off some kick, but wont gum up the gun (*cough* hairspray *cough cough*!)
(currently both my guns are glued at the screw caps b/c of hairspray)

keep in mind its going to be right up next to your ear.

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also how long should it be? i need something that is not going to way a ton

[iknowmy3tables]

how about you make one of the barrels into a chamber
and have an over-under Pneumatic, with a U shape solinod valve, and attach the back thing on with a rubber reducer, and fill it with bateries, ammo storage.

but I bet your still pressed on making him a combustion with two shots, in that case you might want to see if you can find a bell reducer with the small opening shiftted to one side, Ive never seen one for sale, It might be a forgein not in US thing, you might want the encase the back and/or sleve the barrels in case the chamber or barrel is too small, to mantain the outside shape

[BC Pneumatics]

I have heard plans to do this over a dozen times, and I haven't seen one completed yet. Best of luck, I hope something cool comes out of this.

[mindtrickonu]

solving the problem with the same combustion chamber and two barrel is simple ... just install a ball valve behind each barrel so that whichever one you want to fire you leave open ... and close the one you dont ... also what would make this more halo-istic is if you made it to where the second round had to be rotated into position...also able to open up the launcher and be able to take out the chambers (like in the game)

[willarddaniels]

It looks like you have got some great advise on the design. I would add that if you want your friend to continue his excitement over spud guns, get all the stuff together and the two of you build it together. This way he has some genuine ownership, accountability, respect and inscreased thirst for the "sport"