This property specifies whether to fire all the firearms at the same time (= 0, default), or to fire them one by one (= 1). It is used for weapons which have multiple copies of the same weapon, i.e., AddFireArmsPosition is used multiple times for the weapon. This property is set to 1 for the B17's bombs, sub's torpedoes, and the Katyusha rocket launcher, i.e., weapons where the projectiles are fired in a series. In this way, each shot fires from a different position, cycling through the positions defined by AddFireArmsPosition.
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