Pipe label confusion

[RPM314]

Hi, all. Building my launcher, a friend gave me some pipe for the combustion chamber that he didn't need. I just found out that it is probably this stuff:

http://www.lowes.com/pd_23837-1814-PVC+ ... facetInfo=

Is says both foam core and schedule 40. Does anyone know if it's safe?

[Technician1002]

Schedule 40 is a pipe specification for pipe wall thickness. Thick wall does not always equate to pressure rated. Schedule 40 water pipe will have the same dimensions. The difference is the pipe you have is made with a foam layer for light weight vent and drain applications. The page you linked to clearly states it is not for pressure.

The foam thick wall is to give the pipe rigidity so it does not collapse when buried as a drain pipe. It is not for pressure strength.

It is safe if used as intended. Probably not good to use for a chamber.

PVC shatters when it fails. I have tested ABS DWV pipe for lower pressure cannons. See my sig for more info on testing ABS DWV.