What about planes with multiple fixed guns that had different amounts of
ammunition/fire time -- did the pilot have a selector to determine which
guns would fire or did everything fire when the trigger was pulled and some
guns would run out first?

Yes, certainly. You had selector switches.

Because of their limited number of cannon rounds, Japanese Zero pilots
used their rifle-caliber mgs as sighting weapons.

all the best -- Dan Ford
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see the Warbird's Forum at www.warbirdforum.com
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