question about ranger damage

[PopTart]

Playing a ranger, trying to decide which weapon to use and what to leave at home. I have luckily picked up a decent sling, bow, and crossbow and some interesting ammo. The question is:

Rangers get extra shots with the bow, right? Should I take this into account when reading the damage per round for different ammunition while I'm wielding a bow vs. other weapons?

Any other advice about ranged weapons is welcome too. I'm considering carrying the sling for most work because sling ammo doesn't break on use, and then the heavy crossbow for tougher monsters, once I have enough strength to lug it around.