I don't think there are any ranged damage charms, just normal and magic. There is no ranged damage enchantment; the normal damage enchantment gives a ranged bonus when applied to a bow (presumable a damage charm would do the same).
Hi Raze
The only direct damage charm I have seen reads 'melee damage'. That leaves enhancing the magical damage up 24-27 and investing points in Ranger Strength (+1 damage per point - just checked) to up the normal damage.
I definitely suggest putting points in Explosive Arrows as I am now doing between 1100+ explosive fire damage with the chance of igniting anybody still alive. Using 'Ranger Stealth' I can launch that arrow outside of the enemies sight and get a few more off before I start dual wielding.
Add the normal damage to the enemy you aimed at helps. Go for Shamans, Healers, Champions and Bosses. The results are a Blast !!!
How did Larian not include adding normal damage charms or enhancements for bows, Should your bow be a bow with more magical damage and you fire at someone with a high resist you may very well be eating your bow.
Kel******