All I know is that regulators perform better than expansion chambers in certain cases. A Palmer Stabilizer is something I'd suggest if you can afford it. It goes for around $100.
Actually it has nothing to do with "time to expand". It has to do with more surface area to get heat from. It takes heat for liquid co2 to expand to a gas, and it takes the heat from the ambiant air and the surface of the chamber. That is why expansion chambers have many small chambers instead of one large one, so there's more surface area.PaintBallBob said:^^^correct^^^
the expansion chamber just gives the CO2 more time to expand before its shot therefor making your FPS more consistent.