Paintball

[cool0]

good job! the only thing I don't understand is.... why did you turn the gun upside down? what did that prove? or did I read that wrong? also I agree with Mann. turn the velocity down to 250fps(or lower) that way when a spike comes along you are good to go. also Wingman, do you think that dryfiring would help break the gun in?

[brycelarson]

Originally Posted by cool0

good job! the only thing I don't understand is.... why did you turn the gun upside down? what did that prove?

The T8 has a relief valve that would dump pressure if it sucked liquid. the SA doesn't. This is trying to replicate a worst case situation.

[drg]

Originally Posted by brycelarson

The T8 has a relief valve that would dump pressure if it sucked liquid.

Supposedly

[brycelarson]

Originally Posted by drg

Supposedly

right. still waiting for confirmation on that.

[MondoMor]

More precisely, the SA-8 doesn't have a user-adjustable relief. It's set at a fixed pressure. If it did, I likely wouldn't have gotten those ~60fps spikes.

I'd love to see someone do something like this with a TPX, though the method would be obviously different. And a Sydarm...

[brycelarson]

Originally Posted by MondoMor

More precisely, the SA-8 doesn't have a user-adjustable relief. It's set at a fixed pressure. If it did, I likely wouldn't have gotten those ~60fps spikes.

I'd love to see someone do something like this with a TPX, though the method would be obviously different. And a Sydarm...

I've got a TPX. they use a similar system to the Tib guns. it's a dump valve out the back of the reg - you set velocity then lower the dump valve until it just leaks - then tighten it back a touch. With the CO2 up front I would have to shoot up in the air then over the chrono.

and yes, the SA8 will vent at some point I assume - just at pressures that will get the velocity way over 300 fps. I'm curious what the highest pressure the T8's dump valve will allow - or more specifically, how fast it will let the gun shoot.

[Mayvik]

Sounds like between some combination of adjusting the velocity down, filling the extra volume, and lightening the relief valve spring, it should be pretty easy to make these "safe".

[MondoMor]

I wish it was warmer (90F?). And not just because I've got cabin fever. CO2 may be just cool enough not behave badly inside the SA-8 at 75F.

Man, I wish it was easy to take pressure readings of the dump chamber.

[Python]

I bet you could measure the pressure there. Using the two screws on the side, an adapter couple be fashioned to hold in a rubber cork hose adapter. Beyond that, a pressure gauge with enough of an accurate scale around the 800-1100 psi range would be needed. Best bet is digital.

Now you have me thinking...

[Deuce]

Originally Posted by MondoMor

More precisely, the SA-8 doesn't have a user-adjustable relief. It's set at a fixed pressure. If it did, I likely wouldn't have gotten those ~60fps spikes.

I'd love to see someone do something like this with a TPX, though the method would be obviously different. And a Sydarm...

I think the spikes have more to do with the reg springing, and volume chamber. Someone else also mentioned theirs became more efficient after a break in period.