Here's how to read the graph on Warpig. Co2 is very temperature
dependant. The graph is designed to show how filling a tank is related to the
temperature and pressure curve. 

                 Rated fill % by weight of co2
              70%             100%            120%            140% 
temp..........psi..............psi.............psi.............psi
20F...........422..............422.............422.............422
30F...........491..............491.............491.............567
40F...........567..............567.............567............1000
50F...........652..............652.............652............1750
60F...........747..............747.............747............2500
70F...........853..............853............1100............2500+
80F...........969..............969............1500............2500+
88*..........1072.............1200............2000............2500+
100F.........1250.............1400............2500............2500+
110F.........1400.............1700............2500+...........2500+
120F.........1500.............2000............2500+...........2500+

*at saturation point. There is no longer any seperation between the gaseous and
liquid states inside the bottle.

Tanks are rated for 1800 psi @120F- this is why

           As temperature increases, pressure does also. As fill level or rated
fill amount increases, so does pressure again. Co2 is amazing stuff. It can
store latent energy very well. It must be handled with care when filling
bottles because it needs expansion room. As you can see, overfilling a bottle,
even below the saturation point temperature can result in a burst disc blowout,
or a bottle failure. A 140% overfill @ 60F is even enough.
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