Nope. air delivers more FPE than CO2, in the same gun at the same pressure.... CO2 molecules are about 50% heavier than air, and for the same reason that Helium delivers more FPE than air (because it is lighter), CO2 molecules rob more of the available energy to accelerate them than the same volume of air would.... Simply put, a higher percentage of the potentially available power (pressure times bore area times barrel length) is used to accelerate the gas, so less is available to accelerate the projectile.... Bob