Bring a large pot of salted water up to a boil. Add your manicotti shells to the boiling water and cook for about 4-6 minutes until they are partially cooked.
Preheat your smoker to 275 degrees F. While the noodles cook, combine the Italian sausage, cream cheese, BBQ Rub, and mozzarella cheese until combined.
Remove the partially cooked noodles from the water to a cooling rack set on top of a baking sheet lined with foil. Stuff each shell with a portion of the sausage mixture. Grab a couple of ounces of the sausage and roll it into a cylinder shape before sliding it inside the pasta shell.
Wrap each stuffed shell with a slice of bacon, tucking the ends to prevent the bacon from unraveling while they cook. Set the wrapped shells back on the cooling rack.
Place the pan of shotgun shells on the smoker and close the lid. Smoke for about 1 1/2 hours, or until the internal temperature of the sausage reads 170-175 degrees F and the bacon has rendered. Remove the pan of shotgun shells from the smoker.