Well there's your problem.

It only needs maybe 1 1/2 inches, perhaps less.

The piston had a large runup, but it had to stop in rather a small amount of space, there's a lot of force in a piston at full speed, couple that with PVC that's brittle, even more so in low temperatures, and not much of a ...

jackssmirkingrevenge wrote:Part rating and temperature aside, what was your piston travel?

it was around 3-4" from what i remember

well, I'm defiantly gonna go over my next tee more carefully to make sure its not dwv, and that shop vac hose sounds like a good idea, my original bumper was a length of a foam pool 'noodle' but the foam kept getting torn up, which is why i was testing for different bumpers.

the bumper that failed was a garden hose segment, when i was browsing the forums, i saw someone mention using a hose for a bumper, apparently they meant a much thicker hose.

and i stand corrected, the housing / Tee joint, was in fact DWV :( apparently it was mislabeled at HomeDepo as the price ...

long story short, I was testing out bumpers for my 3in barrel sealing piston valve (2in pilot) and well, one of the materials i used didn't stop the piston at all, and it basicly caused the entire piston housing to rupture and explode.
the pressure it was at when I fired it was 75psi, all the parts ...