Buttermilk Biscuits

4 cups of Self Rising Flour
1 tbsp of Baking Powder
½ tsp of Baking Soda
½ tsp of Salt
1/3 cup of Cold Unsalted Butter, cut into small cubes
1/3 cup of Cold Vegetable Shortening, cut into small pieces
1 ½ to 2 cups of Buttermilk
¼ cup of Melted Butter