Preheat oven to 375 degrees F. Mix all dry ingredients together. Cut butter into flour mixture until it resembles cornmeal. Beat the egg slightly into the orange juice; add liquid mixture to dry mix and gently shape dough into a ball. Cut the ball in half, and pat each half out on a floured surface into a circle about 1/2 inch thick, and 8 inches around. Cut into wedges and place on a baking sheet. Bake 15 to 20 minutes, until golden brown.