how much bottle pressure from full 20lb CO2 cylinder?

just got my tank filled and put my reg on for the first time. my tank pressure is at 550psi. is this what i should expect from a full cylinder? it's been a while. i'm only concerned because this pressure is only 50 psi above the red "ORDER GAS" zone.

another question i have: once i've figured out what pressure i need for my desired carb level, i set the reg to that pressure but when i open the gas valve it always drops. should i leave it or do i need to adjust to the pressure i need once the valve is open?

thanks!!

The thing with tanks is they stay at the same pressure until all the liquid is gone then start to drop, that is why the "order" gas is where it is, they thing you should order when you have run out of liquid. The pressure will also be lower if you have it in the fridge.

You should adjust it when everything is open.

My tanks are between 800-1000 full at roughly 75 degrees. At 40 degrees it reads around 600.

My tank will redline on cold nights and damn near greenline on warm days (I keep it outside).

Under almost all conditions, when the tank pressure hits 300 psi, the liquid is gone and you have very little CO2 left.

thanks guys. the 550 reading that i had was right after bringing it inside from the garage. sure enough, this morning it was reading 800. F%&$#ing gas law!