Performances Problems (probably an oversized chamber...)

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Angel-FR
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Thu Nov 23, 2006 1:48 pm

Hello ,
a pict is better than 100 words ,
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this spudgun is really reliable but i shot only 100 metters (about 110 yards) away since with my former spudgun :
Image
this cannon is very smaller and shoted a spud 150 metters away !!

i think the ratio thingy is the problem , i think the best C:B ratio is around 0.7:1 mine is something like 7:1...

here are the spect (all in centimetters , i Live in France) :
chamber diameter : 10
height : 100
volume :

barrel diameter : 4
height : 100

i use hairspray and a one gap ellectronic ignition system
it's a breechloading cannon

I would like to know how i can improve performances , i project to cut my cannon in two part to make 2 cannon :)
cya
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CS
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Thu Nov 23, 2006 2:48 pm

If at all possible id advise you chop 1/2 to 2/3 of your chamer and replace with a female adapter and cap, or whatever device you have to access the chamber. Also add some barrel length, total of 5-6 feet in length. You got several things you have to balance out, I mean your total length cant be to long as to remain portable. So id suggest you find a comfortable length that will work for you, then figure out a ~1:1 ratio for the gun. Yea the chamber on the gun pictured is WAY to big. Any more questions be sure to ask.
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SpudStuff
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Thu Nov 23, 2006 3:39 pm

Woa. The problem is you are using hairspray! You should switch to something better. Like oh say Stating Fluid! For a chamber that big you need maby 2-3 seconds. And a chamber fan would help ALOT. If mixes the fuel and vents the chamber when you are done with the shot.
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Angel-FR
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Thu Nov 23, 2006 3:51 pm

pimpmann22 wrote:If at all possible id advise you chop 1/2 to 2/3 of your chamer and replace with a female adapter and cap, or whatever device you have to access the chamber. Also add some barrel length, total of 5-6 feet in length. You got several things you have to balance out, I mean your total length cant be to long as to remain portable. So id suggest you find a comfortable length that will work for you, then figure out a ~1:1 ratio for the gun. Yea the chamber on the gun pictured is WAY to big. Any more questions be sure to ask.
OK thanks for your help , so if i shorten the chamber to reach about 30 cm , so i will get a ratio of 2:1 that would be good or i should try 15 cm for a ratio of 1:1 ,what's the best to have good performances ?
that will be a very very little chamber , it's going to be hard to put the good amount of gaz in it :/
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