The passion of the 31st round, "Low temperature is a GBB killer."
 
Some user test G5 in cold weather (around 10℃) and found that the power of shoot did not level down no matter semi or auto mode. It is accepted by everyone that G5 has good performance of gas efficiency.
 
In fact, the development of G5 use concept of GHK PDW started from two years ago; and the whole idea is around upgrading gas efficiency. But the test result could never reach the goal: it always failure after the 31st bullet shooting...