Easy.
Sometimes, when loading a game, or when clicking after dying waiting to respawn, your game will load but your gun will start shooting non-stop. This is not that big of an issue, except when you are low on ammo. To make sure this doesn’t happen do the following:
If you died press a keyboard key to respawn, instead of clicking.
If you want to load a game select it with your mouse, but open it with the Enter key.
That’s it, hope you enjoyed