1. In a large bowl, combine meat, paprika, brown sugar, salt, black pepper, cinnamon, bread crumbs, onion, oil, and egg. Form mixture into ping-pong-size balls.
2. In a medium saucepan over medium heat, combine ketchup, blueberry preserves, and grape juice. Bring to a boil.
3. Drop in meatballs. Lower heat and cover. Cook for about 45 minutes, checking periodically. If mixture seems to be burning, lower heat further. Serve warm or at room temperature.