[Johnny Ringo]

CO2 tank covers only protect the tank from damage and the users from frostbite.

CO2 comes in solid, liquid and gas--we use liquid and gas. You don't want to use liquid--it's dangerous. Liquid boils into gas going to your valve and increases the pressure (aka velocity). Seals can also be damaged. That's why you anti-siphon CO2 tanks (crimping them just improves your chances of not drawing in any liquid).
CO2 pressure is only determined by temperature. Low temp equals low pressure (inconsistent velocities) and high temp equals high pressure (too much, of course, being dangerous to you and your marker).

You fire some CO2 gas and the tank's pressure drops.
Liquid CO2 then boils/expands/evaporates into gas (chilling itself and losing heat only lowers the pressure even more and further lengthens time to re-pressurize [expansion rate])*.
Gas CO2 re-pressurizes the tank.

*Notice the vicious cycle? The more you fire, the more you chill the tank, the more you lower the pressure and the longer to return to operating pressure/liquid expansion into gas. Mix in cold weather and getting back to your operating pressure is not instantaneous.

Covers/socks/handwarmers/KY/solar blankets will not be able to compete with this quick chilling cycle in the long run. Better to understand the physics of CO2 and play your game according to it's game. (My logic may not be without fault here, but it's only the concept that needs to be understood. I realize we want to have better results but this is the way that the cold air has on our equipment.

What?:popcorn: