Can military guns be used normally in extremely cold weather?

Military guns will be tested in various environments, such as low temperature, high temperature, dust and corrosion. , and the military requirements of the temperature range is plus or minus 50 degrees, because generally not more than all parts of China, extremely cold weather may not be able to use. The performance of steel will be greatly reduced at low temperature, and it is easy to break, even at ordinary low temperature. After all, there are individual differences in parts!