In a greased slow cooker, add the drumsticks and the dry rub. Coat the drumsticks evenly with the rub and work it in with your hands.
Add in 1 cup of the bbq sauce and cook on LOW for 6-7 hours.
Once the 6-7 hours is up, remove from the slow cooker and place on a sheet pan. Add 1/4 cup more bbq sauce on top and brush all over the drumsticks. Place under the broiler for about 2 minutes, or until the sauce thickens and turns into a glaze. Enjoy!