Just kind of feel overwhelmed about all the choices for ammo and stuff. Right now I'm just sticking with normal ammo for all, and see how far that can take me.
Here is some advice, once you can start carrying good amounts of ap / hp rounds, for guns that have both this type, just stop carrying regular ammo and don't pick it up when you find it. Once you start understanding how ammo works, get handloader perk (you won't regret it) as you will be able to make special ammunition types that do much more damage and sometimes have no decay penalties, but some do have weapon decay penalties.
I like to kill my enemies as fast as possible and I feel like regular ammo (for most types of guns) doesn't cut it. But there are exceptions of course.
If your using energy weapons, you might want to consider making maxed charged ammo which requires high science, it has heavy decay penalties but I want to kill my enemy in one shot, not 3-4.