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PelletPutter2 · New Member

I have a 1077 Crosman rifle that I had modified a couple years ago,in order to have more co2 capacity. I also included a pressure gauge. I have several 9oz. co2 bottles that I use to refill the gun. I get the bottles refilled at a local Sports Authority store. In the past, a newly charged bottle would give me 920 psi into the gun. I recently had the bottles refilled & now I only get 800 psi into the gun.
My question is : Did I get cheated out of a full refill? And would the difference of 120 psi have much of an impact on the range that the pellet would travel? If so, I would have the bottles recharged. Sometimes these store clerks leave a bit to be desired.
Thanks for any input on this subject .....

Slavia · Moderator

The CO2 is stored as a liquid, and the vapor pressure of the gas that boils off is related to temperature. For any given temperature the gas pressure should always be the same. Maybe your gauge is taking a siesta, or perhaps you checked the pressure at two different temperatures?

Look at the opening page when you first arrive at airgunhome, and you will find a calculator for CO2 pressure vs. temperature.

ZipSnipe · Veteran Member

how bout a pic of your set up?

PelletPutter2 · New Member

Thanks for the reply. I guess it could be a temp issue, however, this last refill was the only time I have ever seen gauge go below 920 from a full bottle. As I use up each bottle, I'll check to see if they are all reading the same. I fill the gun at home & the room temp is pretty much constant.
As for a pic , I don't have much to offer, but here's a couple shots. Not much to brag about...........