Patent attributes
Firearms with improved systems and methods of controlling which side of the firearm shell casings are ejected from, with ejection port covers on both sides of the firearm that open to provide cross ventilation, or both. In some embodiments, the bolt can be installed in one of two different orientations to select whether shell casings are ejected from the left or the right ejection port without a need to replace any parts. In a number of embodiments, spring loaded ejection port covers on both sides open when the firearm is fired or when the bolt or carrier of the firearm moves to provide cross ventilation through a passageway through the firearm to cool the firearm. The covers can be manually closed by the operator when the weapon is not being fired to keep dirt and debris out of the firearm.
