ist all good ,about the ball valva i went to bunnings the other day and got a sprinkler valve and modded it with a blow gun,it awsome now steady as a rock...and accurate ill post a pic tommorow its 11.00pm ..inonickname wrote:I'm gonna have to agree...you are spending a bit on this. My gun, which I will post tomorrow has had less than $100 spent on it (actually, perhaps more), including making a homemade 400 psi pump.
You can buy a $3 laser pointer from a store, carry out a simple mod on it to make it remotely switchable and put a nice case on it for aesthetics. Probably all under $5, presuming you had none of the parts (switch, wires etc to begin with)
By the way, with a ballvalve you will throw your aim off trying to open the valve fast.
Sorry to sound so critical, but it is actually quite a nice gun
first attemp at pneumatic cannon>>>swooshhhhhh
Last edited by FORE!!!! on Fri Jul 17, 2009 8:05 am, edited 1 time in total.
and the vinly was used for another project of mine not this one ,i wraped my laptop shell with it and had leftr overs...frozebyte wrote:Don't think it was necessary to spend the 50bucks on a carbon fiber vinyl to strengthen your pvc pipe. That amount could've built you a nice copper gun or two.
Considered saving those for another project?
could've saved those leftovers for a sleek spudgun, i think the carbon fiber would make even a pvc gun look super sleek like a copper one
Oh i forgot you weren't a fan of small copper spuds, right? not nitpicking but you could quote twice in a post :]
Any progression for a next spud? can't wait :] you have pretty nice extras (cause you've got the cash)
Oh i forgot you weren't a fan of small copper spuds, right? not nitpicking but you could quote twice in a post :]
Any progression for a next spud? can't wait :] you have pretty nice extras (cause you've got the cash)
just an update to my last post, the modded sprinkler valve and a damage shot...
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- 20mm thick particle board
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- exit wound...
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- the target entry hole next to bullseye,this was my first attemp at the target
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- full view
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- new valve,,had to mod it on side of caseing because of guide rod..
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jackssmirkingrevenge
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Shame the chamber is still so big relative to the barrel, you're getting a lot of extra noise and filling effort without any real performance benefit.
just wondering weather this would be an exceptable chamber lenght?
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- full lenght ==chamber 700mm including tee elbow,,barrel lenght=950mm have i gone too far?
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- x2 45 degree bends,, and x1 end cap
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- bored.
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jackssmirkingrevenge
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Not far enough in my view, capping the Tee with no extra pipe is enough.Have I gone too far?
Of course more chamber = more power but it gets to a point where you might increase chamber volume to 200% and get a power increase of 2%, ie not worth it. It depends what you want. I personally would chose silence and convenience.
Have you tried plugging a few numbers into GGDT to get an idea of what sort of performance increase/decrease you're talking about?
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jackssmirkingrevenge
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Set to Generic, Flow coef 30 and opening time say 10ms.
Input all the correct data (barrel length, pressure, calibre, projectile weight etc.) and start with a chamber length of 10 inches.
Make note of the muzzle energy, then check it with 11 inches, 12 inches etc until you reach the length of the barrel.
This way, you'll get an idea of how performance changes with more volume and you can make an informed decision on what your ideal chamber volume should be
Input all the correct data (barrel length, pressure, calibre, projectile weight etc.) and start with a chamber length of 10 inches.
Make note of the muzzle energy, then check it with 11 inches, 12 inches etc until you reach the length of the barrel.
This way, you'll get an idea of how performance changes with more volume and you can make an informed decision on what your ideal chamber volume should be
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jackssmirkingrevenge
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If I'm not mistaken (don't have GGDT at work 
) go to the configuration window and change your linear dimensions to inches.
Anyway it's not relevant for the purpose of this exercise, just make a list of chamber length and the corresponding muzzle energy.
Test at the pressure you typically use.
) go to the configuration window and change your linear dimensions to inches. Anyway it's not relevant for the purpose of this exercise, just make a list of chamber length and the corresponding muzzle energy.
Test at the pressure you typically use.