Grenade Launcher Too Small?

Boom! The classic potato gun harnesses the combustion of flammable vapor. Show us your combustion spud gun and discuss fuels, ratios, safety, ignition systems, tools, and more.
Phil23
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Sun Aug 31, 2008 3:20 pm

Hey, I'm new here at SpudFiles. I built my first cannon when I was playing airsoft and saw this cool "Bazooka". That's sparked me (no pun indented) to make my first combustion cannon. After that, I built some other small ones and they where all huge and sucked balls. :D

Now I want to make a small grenade launcher. What I first thought of was just a small combustion cannon. Just have a barrel and a BBQ ignite and it'll work perfectly, or so I thought. :roll: Searched around and found out that it may be a hazard that having such a short barrel would cause a problem. I just want to confirm this isn't a problem before I start.


EDIT: Also, I'll be shooting 1.75 inch foam balls. Not BBs. And the launcher will be approximately 12-15 inches made out of 1.5 inch PVC.
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MaxuS the 2nd
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Sun Aug 31, 2008 3:34 pm

I think that a pneumatic would be better suited to that kind of application.

A longer barrel helps with accuracy and velocity but most spudgun' barrels are a trade between efficiency and portability/comfortability (a word?).

12-15" is pretty damn short even for a small combustion, unless of course you mean that's the barrel length. This would make fuelling quite difficult without a doubt. I suggest you use a pneumatic. :P
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Phil23
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Sun Aug 31, 2008 8:47 pm

MaxuS the 2nd wrote:I think that a pneumatic would be better suited to that kind of application.

A longer barrel helps with accuracy and velocity but most spudgun' barrels are a trade between efficiency and portability/comfortability (a word?).

12-15" is pretty damn short even for a small combustion, unless of course you mean that's the barrel length. This would make fuelling quite difficult without a doubt. I suggest you use a pneumatic. :P
Thanks for reply. :D Yeah, I've made a pneumatic gun before but it was really bulky. How would you get enough air to make it fire like I would want?
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VH_man
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Sun Aug 31, 2008 8:49 pm

search up DavidVani's Burst Disk Cartriges. They are EXACTLY what you want. he even shoots nerf balls out of them........
Phil23
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Sun Aug 31, 2008 8:56 pm

VH_man wrote:search up DavidVani's Burst Disk Cartriges. They are EXACTLY what you want. he even shoots nerf balls out of them........
Yeah, I saw it on ASF.com and saw it here, but it went way over my head...I don't get exactly how a burst disk works. I mean, I was reading it and everyone was saying, "Oh! This is so simple!" and just made me feel more embarrassed. :oops: So I thought I would just skip it. Probably easier just to look it over?
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VH_man
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Sun Aug 31, 2008 8:57 pm

look it over a few times. PM me if you have any questions. when you figure it out, youll be kicking yourself........
Phil23
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Sun Aug 31, 2008 9:09 pm

^ Thanks man for the help. I'm kicking myself now. :D
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jimmy101
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Mon Sep 01, 2008 6:38 pm

So, you are trying to make short combustion gun, with a single pipe for both chamber and barrel, to fire a very low mass and low friction ammo.

You'll want a pretty small chamber, as small as CB 0.5 or perhaps even less. Since you can ram the ammo to any point you want, the gun has an infinetely adjustable CB.

A chamber fan always helps, as does any type of fuel meter.

If you donwload HGDT you can fiddle with the CB to get an idea of the best way to partition they gun into chamber and barrel.
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jackssmirkingrevenge
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Mon Sep 01, 2008 11:24 pm

MaxuS the 2nd wrote:A longer barrel helps with accuracy and velocity but most spudgun' barrels are a trade between efficiency and portability/comfortability (a word?).
Ergonomics, perhaps?

Remember, you're in the UK, not in the US, you don't get to construtisize your own verbical structurizationality ;)
hectmarr wrote:You have to make many weapons, because this field is long and short life
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