pressure rating

[b-nice]

would a 4'' * 24'' chamber be to much to use nsf-dwv fittings

[spudshot]

4" pressure rated pipe is fine for pneumatic or combustion, though you shouldnt use NSF-DWV fittings on anything but combustions, NSF-PW fittings are the correct type for pneumatic cannons

[boilingleadbath]

I thought you'd be a little more cautious, spudshot, science devilsmed69 had a chamber failure; at least going as far as to say that DWV isn't <i>recomended</i> for combustions...

[spudshot]

i woudnt say that, DWV fittings have been used on combustions for years, the only thing you shouldnt have DWV on a combustion is your pipe and your plug, cleanout plugs can and will shatter very easily, get an NSF PW plug or combine a male adapter and a plug

[b-nice]

i use a 2'' plug with the hex end shaved smooth and insert the factory edge into the chamber and the other to my handle

[Bedo]

im not sure if this is a dumb question
im buying a 3" to 1" bushing off mcmaster and it says it is NSF-61(im lookin for NSF-PW...of course) is that the same thing as NSF-PW or what? plz help

[boilingleadbath]

Tecnicaly, it's not - NSF-61 only rates for health effects.
However, the construction of them is robust and the socket lengths long, so it should be fine for pressure... which makes scence, as most water for consumption is under pressure in the lines.