1. In a large saucepan, over medium-high heat, combine blueberries, 1/2 cup sugar, cornstarch, and lemon juice. Cook, stirring constantly, until mixture thickens and comes to a boil. This takes about five minutes. Boil out one minute. Remove from heat. Set aside.
2. Prepare pie crust according to double crust directions. Fill lower crust with blueberry mixture. Brush top crust with milk and sprinkle with remaining sugar.
3. Place on a cookie sheet and bake in a preheated 400 degree oven for 25 minutes or until crust is golden brown and blueberries are bubbly. Cover edges with aluminum foil if needed to keep from over browning.
4. Remove from oven and allow pie to cool completely.