In a bowl, combine shredded papaya and 2 tablespoons of the salt. Allow to sit for about 1 hour or until papaya begins to release liquid. Place papaya in a cheesecloth and squeeze firmly to dispel juices.
In a sauce pot over medium heat, combine vinegar, sugar and the remaining 1 teaspoon of salt. Bring to a simmer and cook, stirring occasionally, for about 3 to 5 minutes or until sugar and salt are dissolved. Add ginger, onions, garlic and peppercorns. Continue to cook for about 2 to 3 minutes.
In a bowl, combine papaya, bell peppers, carrots and raisins. Add pickling solution and toss gently to combine. In a sterilized jar, transfer atchara and close with tight-fitting lid. Refrigerate for 1 to 2 days to allow flavors to develop before serving.