SpudFiles

hi am working on a sniper that works on 88g co2 capsules. my idea was to use a sprinkler valve as primer valve. i know that a 88g CO2 capsules has 50BAR (800psi) on it. can my sprikler valve hold it or wil it explode.

plz help.

JJ pyro wrote:hi am working on a sniper that works on 88g co2 capsules. my idea was to use a sprinkler valve as primer valve. i know that a 88g CO2 capsules has 50BAR (800psi) on it. can my sprikler valve hold it or wil it explode.

plz help.

Sprinkler valves are only rated to 150psi. They have been taken higher but it's a bad idea.

Remember, that CO2 cartridge is at 800psi, but when you let it expand into a larger chamber, the pressure will be much lower.

Somewhere on Spudfiles there's a chart that tells you what PSI a CO2 cartridge will fill a certain chamber volume to.

The real problem isn't the pressure - it's the extreme cold. CO2 gets very cold when it expands, which makes PVC pipe very brittle - so it's best to use a metal expansion chamber.

I'll try to find you that chart. You'll need a chamber, I'm guessing, about 10" to a foot long, 1.5" - 2" in diameter for a safe margin, but that's just a guess.

Peace,
Pete Zaria.

this chart is for a 12 gram cartridge. For an 88 gram cartridge you're looking at a 220 cubic inch chamber to be reasonably safe, that's 70 inches of 2" pipe - which using a sprinkler should give you more than one shot per cartridge.

My advice would be to use a couple of chambers. Have one high pressure one, made of metal and then have that fill a smaller PVC chamber through a regulator. That way you lesson the affect of the coldness and although the liquid to form into a gas. Although I guess now you need a reg.

Where did you find an 88 gram CO2 cartridge?

benstern wrote:Where did you find an 88 gram CO2 cartridge?

They're quite common as longer lasting alternatives to 12 grams.

Sorta usless and money comsuming, but a bike pump, it will pay for itself in a FREE air/power supply.

Unless you want to get multiple shots out of it, a co2 cartridge isnt nessasary (if you do want multiple shots, a homemade spud/nerf gun here uses them, it gets 20 shots per cartrige with a range of 100feet)

here

http://www.boltsniper.com/BS-1/BS1.htm

Or if you really want to get cheap, make a blow gun!

hahaha nerf blowguns are great. i can own anyone with my nerf blowgun.......

its accurate, powerful (ive left welts) and has a High ROF.

my idea was to dril a hole in the arm thing and put the co2 cartrig in it. connect it to a co2 adapter and connect it to a bal vavle with a preseure meter. and then to the sprinkler valve. wil it simply explode or wil it fier hard

sorry for the bad grammar but i am a 13year old dutch boy

For CO2, you should use a regulator if you dont want the gun to explode

Why not just pump it up with a bike pump or something like that?

JJ pyro wrote:hi am working on a sniper that works on 88g co2 capsules. my idea was to use a sprinkler valve as primer valve. i know that a 88g CO2 capsules has 50BAR (800psi) on it. can my sprikler valve hold it or wil it explode.

plz help.

a sprinkler valve will not handle that kind of pressure but this one will.
http://www.vtkustoms.com/GC800.html

i guess this is a little off topic, but i really didnt wanna have to make a whole new post for just 1 question.

Whats the formula for figuring out what pressure CO2 will give you at a given volume. The one given for the 12g is a simplified one, and i would like to mess around with different size cartridges/pressures/chambers.
It looks like (edit.... JSR... not FMJ... i guess im still living in the past) knows this...

The sprinkler valve I use (1" Orbit), is rated to 80 PSI, I've taken it to ~110 PSI without incident.

You definitely want to make sure the pressure behind it doesn't exceed 100 PSI.