Camping 14 (Source)

You heal at a rate of 10 wounds for every 5-6 minutes in a camp, with the first heal coming after 6 minutes. This was changed in late Beta from an early heal to prevent folks from repeatedly building camps to heal wounds faster. There is no limit to wounds healed by the camp, but I believe there is about a 30 minute timer on the camp itself before it disbands automatically.

Higher-level camps (Ranger camps) are supposed to heal wounds at a faster rate, but there is no practical difference in wound healing based upon camp level currently. Expect this to change in the future, and perhaps for camp wound healing itself to be nerfed to some extent - at least that was the talk in late Beta.