The game engine is on a RPG engine. Therefore, it is more turn/volley based rather than per shot based. Every time you fire, you essential make a roll for damage, like in the old school tabletop RPGs. You add in your damage skills, your items, plus your position, and any buffs that are applied to you. This is your attack power in that roll. Then, your target applies their defensive skills, items, and defensive buffs. The Two are mashed together into the program, and the damage is dealt. Rinse and repeat per shot. (Roughly... I actually have little idea how the combat system works in this game. But based off my limited knowledge, it is something like this.)
The entire game mechanic is based off this from the floor up. The Shooter mode was just a patch on top of this system to make the interface slicker.
If you want to make the shots more realistic, either we can strip the game down and rebuild the combat system from scratch. In which case, might as well make a whole new game at that point.