Mjolnir

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pigion
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Fri Mar 09, 2007 11:02 am

Well here go’s :D

My first pneumatic cannon. I named it Mjolnir (after the hammer of Thor). It is completely made out of copper and brass pieces. It took me about 3 weeks to build and a lot of checking for leaks. The whole thing cost about 175 Euros.

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The valve configuration works with 2 ¾ QEV valve’s, I can trigger them with the ball valve or the blow gun.

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The barrel is a piece of 22mm copper with a length of 2 meter. I shoot pieces of lead or marbles with it.

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I have taken it up to 10 bar with a bike pump (the pump is capable of 18 bar or 260 psi). I made it from copper because it can take much more pressure than PVC and I feel more save around it.

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So what do you think?
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Hotwired
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Fri Mar 09, 2007 11:31 am

The chamber setup is a bit odd but whatever floats your boat :D

It looks very unportable but I'd imagine it has some serious power with a barrel that long. I'm guessing 2m+?

Is the pointy metal slug thing its ammo? It looks lethal.
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Brian the brain
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Fri Mar 09, 2007 12:01 pm

Great way of increasing flow while keeping the incredibly fast opening of the QEV's. The whole thing looks awkward (sp?) but also very focused on result.
You can use more pressure , the valves can take more than they are rated for.
Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!

Can't ask for a better compliment!!
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Hotwired
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Fri Mar 09, 2007 12:06 pm

Yeah, I've seen those types of QEV said to be safe to 300psi and you can have my word that they're fine at 200psi.
Matheusilla
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Fri Mar 09, 2007 12:38 pm

I see those small QEV's on a lot of copper canons; what is their original application? I'd like to know so that I can find some for myself, they're quite intriguing (if no one minds tellin' me...)
pigion
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Fri Mar 09, 2007 1:18 pm

I have made it just to preform thats why I didn't care for portability ( I'm not gonna walk around with this thing on public streets :D
I haven't shot it over a chrony so I don't have a idea at what sort of speed the projectile travels (it is faster than my airgun and that gun shoots at aprox 200 m/s
The camber is a bit weird I know but so am I
The projectile in the picture is custom made from aluminium, I use it to make lead projectiles the little thing next to it is a bullit or pellet from my airgun
I'm happy to hear that the QEV can take more pressure I will certainly try it at 15 bar
The QEV (quick exhaust valve) are used in combination with pneumatic cylinders) correct me if I'm wrong the language diffrecence may make my explanation a bit hard to follow :( )
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medievalman
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Fri Mar 09, 2007 3:12 pm

That looks like a really powerful gun! Glad that you can be creative and not comprimise your, well...um, "artistic style" for power.
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spudthug
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Fri Mar 09, 2007 3:22 pm

no u said it right but anyway ur gun looks a bit akward isnt it hard to fill with that wierd chamber??
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MrCrowley
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Fri Mar 09, 2007 3:37 pm

That thing is a beast! Good job.
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Fnord
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Fri Mar 09, 2007 4:58 pm

Nice gun, and very... interesting design.
Is it a bad thing that I actually knew what mjolnir was before I read the description?
pigion
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Sat Mar 10, 2007 2:31 am

spudthug wrote:no u said it right but anyway ur gun looks a bit akward isnt it hard to fill with that wierd chamber??
No, it doesn't matter how you make the chamber as long as you don't create any bottle necks, why would it be hard to fill? :?

The camber looks weird because I had to make a choise; I could search for a bigger pipe like 35 mm or use more 22mm pipe. The second option was the cheap option so I did it that way.
The amount of chamber is very important with a long barrel if you dont have enough chamber the pressure will drop as the projectile travels down the barrel. This can create a vacuum behind the projectile slowing it down or a low pressure canceling the advantage af a long barrel.
_Fnord wrote:Nice gun, and very... interesting design.
Is it a bad thing that I actually knew what mjolnir was before I read the description?
No it is not a bad thing :D it's a good thing actually, but some people just don't know what Mjolnir is.
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CpTn_lAw
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Sat Mar 10, 2007 4:26 am

could you tell me what it means? Mjolnir? Is that russian?
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MrCrowley
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Sat Mar 10, 2007 4:40 am

pigion wrote:My first pneumatic cannon. I named it Mjolnir (after the hammer of Thor).
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