Firing any firearm generates a very high temperature in the firearm's barrel and elevated temperature throughout much of its structure. If fired too fast, the components of the firearm will suffer a structural failure. This means that all firearms, regardless of whether they are semi-automatic, fully automatic, or burst mode in their firing methods, will overheat and fail if fired too often. This is especially a problem with fully automatic fire. In actual use (for example the MG34), a gun might be able to fire at 1200 rounds per minute, but in one minute it may also overheat and fail. So guns used in a repeated firing mode must not be fired too often. The MG34 is fired manually in bursts of 5 to 7 rounds (no automatic disconnector mode in this gun). It can fire at an effective rate of 150 rounds per minute.