Ammo drop seems fine, considering you'll be using the ammo much more early on. In our game we get a surplus of ammo, because of me having high values in Lucky Looter and reading that ammo loot magazine early on. Maybe a slight bit too much ammo drops, but... so it's hard to say for us if it's too much, but yes we do end up with a lot and got a lot of ammo rewards from the trader early on too.
Now those endless Q6 Pipe Machine Gun drops though.... What's up with that?