I'm considering using a 1 metre long (that's approx. 3 1/4 foot for you Americans!) piece of 16mm PVC pipe as a barrel for a marble sniper and am just wondering if anyone knows what sort of pressure it would be able to withstand- like would it still be happy above 200psi. or would I be better off trying to find something in metal (I know copper doesn't come in a size which fits marbles as well, so are there other metal tubings manufactured, which are easily available in Australia which are this size)
Thanks.
p.s. sorry if this has already been discussed, but I DID search for it and nothing matched this!
Barrel strength
where do ya live i got Stainless steel 16mm I-D tube lol 
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jackssmirkingrevenge
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It should be fine, unlike chambers barrels only have to withstand pressure for a brief fraction of a second, and given the way pneumatics develop their power the chances of a barrel failure are minute.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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super spuder
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it depends if the pipe is presure rated and what it is presure rated to (example sch40 sch80)
Super spudder, not really.
To be redundant, barrels really don't hold very much pressure. There is force exerted on the barrel for a small fraction of a second, which isn't enough to make it burst, unless there's hundreds of psi being shot from a huge chamber into a small, thin walled barrel with an extremely tight fitting projectile.
To be redundant, barrels really don't hold very much pressure. There is force exerted on the barrel for a small fraction of a second, which isn't enough to make it burst, unless there's hundreds of psi being shot from a huge chamber into a small, thin walled barrel with an extremely tight fitting projectile.
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super spuder
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he did not really say how big the chamber was. but the barel is 16 mm wich is kinda small. and dont marbles fit fairly tight in 16 mm pipe (i am not sure cause i have never made one) but you are probly right, cause it is only 3 1/4 feet long and uless he is using a large chamber and wasting alot of air the chamber is probly not verry big
the chamber is probly not verry big
Last edited by super spuder on Sun Apr 22, 2007 7:36 pm, edited 1 time in total.
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rna_duelers
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He mean 3'3".But still a sudden pressure spike in certain conditions wouldn't be a whole lot of fun as I found out.I had a Class 12 25mm pipe(170spi) barrel rupture when fired in cold weather and cold for me were I live is about 15'C.
The 16mm pipe you are using is it electrical PVC?As that pipe is the best fit for marbles and the wall thickness is thicker then 15mm Class18 pipe so a burst from that barrel would be very unlikely unless i9s cold weather and with high pressure.
The 16mm pipe you are using is it electrical PVC?As that pipe is the best fit for marbles and the wall thickness is thicker then 15mm Class18 pipe so a burst from that barrel would be very unlikely unless i9s cold weather and with high pressure.
hey yeah I'm pretty sure it's electrical tubing, with 2mm thick side walls.
and I won't be using too excessive an amount of air (chamber) like the ratio isn't prob. gonna be more then 2:1 at the most, thanks for the responses by the way guys, yeah 15'C is about the coldest it gets where I am.
and I won't be using too excessive an amount of air (chamber) like the ratio isn't prob. gonna be more then 2:1 at the most, thanks for the responses by the way guys, yeah 15'C is about the coldest it gets where I am.
It depends on the configuration of the gun. If you're making a coaxial I wouldn't take it to 200psi with pvc or the barrel could quite easily be destroyed. Not really a safety concern because it will collapse inwards but a waste of money.
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jackssmirkingrevenge
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I've used 20mm PVC electrical conduit (17mm I/D) as a barrel in coaxials at up to 400 psi, never had a failure.cerberus wrote:It depends on the configuration of the gun. If you're making a coaxial I wouldn't take it to 200psi with pvc or the barrel could quite easily be destroyed. Not really a safety concern because it will collapse inwards but a waste of money.
hectmarr wrote:You have to make many weapons, because this field is long and short life
I stand corrected. I was making an assumption based on the fact that the PVC is generally rated for 160psi and thats assuming the pressure is on the inside of the pipe. That being said, 160psi leaves a fairly large safety margin and I can't really see why the rating would be any less for external pressure, so listen to those with experience.