In a small bowl, whisk together the egg and milk and set aside. 

Peel, core, and slice the apples into 1/4-inch thick wedges. 

Place apples in a large bowl and mix with 1/4 cup flour, 1/3 cup sugar, cinnamon, 1/4 teaspoon salt, and lemon juice. 

Fill the bottom pie crust with the apple mixture, packing apple slices as tightly as possible.

Brush the rim with egg and milk mixture, reserving the excess. 

Top pie with the second pie crust press over apples to minimize excess space between apples and crust. 

Press the top and bottom crusts together and trim the top crust to a 1-inch edge around pan. 

Tuck top edge under bottom edge and crimp. 

Cut five vents in the top crust for steam. Refrigerate pie for 30 minutes to set the crimp.

Brush top crust with egg wash. 

Place pie on a preheated rimmed baking sheet and bake until the crust begins to turn golden, 20 to 25 minutes. 

Rotate sheet, move to center rack, and reduce oven to 350°F. Continue baking until the crust is golden brown and you can see the apple mixture bubbling, an additional 40 to 50 minutes. 

Cool on a rack 3 to 4 hours to allow pie to set before slicing.