bald man in a boat wrote...
I was wondering if the weapon sounds start off as foley elements and then get morphed from there?
Not sure what you mean by this, but I'm guessing you're asking if we use real-world recorded sounds as the base for the weapons?
Most guns have a few different layers in them: mechanical, tone, body, bass, and environmental response. Often the "body" layer will be some part of a real weapon recording - this gives you a core to work from and helps ground the gun in reality. From there we are free to play around with the other layers, adding colour and perspective. You'd be surprised at some of the weird stuff we throw in there

Much consideration is given to the lore of the weapon as well; we usually try to make the different technologies feel like the races that created them.
Of course some of the weapons are purely energy based so all the rules go out the window. I've had a few sleepless nights trying to figure out what a laser gun should sound like from far away... pew pew pew?