Making Double Firing Cannons

This tip is really easy to do.  For example, the F-5A has a pair of M39 Pontiac guns.  Well how do you get them to fire as one.  So basically not having to switch from one gun to the other.  It's simple, so very simple.  When you set the hardpoint, set all your variables and then select Symmetrical Loading and then when you fire, you'll get a pair of cannons to rip the enemy to shreads.