dwv pressures

[sprayandprayboy]

nuthing fancy ive just built my first pneumatic gun... chamber - 8"X 3" dwv
barrel-1/2"X 18" my question is what will a safe working pressure be

thanks

[Mr.Tallahassee]

I wouldn't hardly trust it past 30psi. DWV is not pressure rated so safety is a major issue. Scrap the chamber and use pressure rated if possible. Does it say nsf-pw anywhere on the pipe?

[pneumaticcannons]

If the pipe itself is dwv/foam core then I seriously wouldn't go beyond 20 psi. plus you should scrap the chamber without a doubt. If the fittings are dwv but feel fairly solid it should be fairly safe for lower pressures (70-80) psi

[DYI]

"Fairly" is a weasel word which is best avoided when considering the probability of receiving severe injuries. If the gun is handheld, either use parts rated for the operating pressure level, or hydro-test the entire system to the operating pressure multiplied by your safety factor. Although firearms cannot afford this luxury, a safety factor of two or three is readily achievable and desirable with homemade low pressure gas guns.

[Technician1002]

My question is PVC or ABS. I made a test cannon with ABS DWV. Tried to blow it up and failed. See my sig for the link to the ABS test cannon. Your results may vary.

DWV Cell core testing to 100 PSI. 4 inch pipe. Pipe is clearly marked ABS CELLULAR CORE DWV. Tested at 100 PSI. Used at ~60 PSI.

[sprayandprayboy]

this was mostly a learning experiance for me than it being a serious gun i may build a high pressure gun from black steel pipe i just wanted to know what safe pressures i should test at ill stay below 30 psi
thanks

[Gun Freak]

One of my friends built a cannon with DWV fittings and it blew around 60 psi, so just be careful, make sure you stay really low.

[sprayandprayboy]

One of my friends built a cannon with DWV fittings and it blew around 60 psi, so just be careful, make sure you stay really low.

ok thank you but this was just an experiment ... my first airgun

[mark.f]

First off...

I don't think anybody really realized that chamber is kind of stupidly big for such a small barrel.

Smaller, pressure rated fittings could be used for the chamber and wind up costing less. 2" or 1.5" PVC and fittings are available pressure rated from most stores and will be cheaper than 2" fittings (even DWV ones).

[sprayandprayboy]

First off...

I don't think anybody really realized that chamber is kind of stupidly big for such a small barrel.

my c:b is is outragous because im using a ball valve

[jsefcik]

just buy all parts from lowes or home depot im pretty sure all the pipe there is pressure rated

again im pretty sure still check , dont jump down my throat if im wrong( mr crowley gunfreak warhead) you guys know who you are

my first air cannon was all dmv, but i didnt know what i was doing, but i took it up 120 psi nothing wrong, no leaks no nothing if it blew prob from a leak

[sprayandprayboy]

my pipe is from lowes but i dont have access to the piece with the specs

[jsefcik]

my pipe is from lowes but i dont have access to the piece with the specs

check the fittings they should say nsf pw then

[sprayandprayboy]

[quote="jsefcik"

check the fittings they should say nsf pw then[/quote]
they say nsf

[Gun Freak]

my first air cannon was all dmv

I'm not sure you'd be allowed in the DMV with a cannon

they say nsf

They should also say PW meaning potable water. If they say NSF-DWV then don't use them.