My father has 2 1100's that are magnums. They both fire 2 3/4 and 3 inch shells with no problems. There was a couple of years that Remington made the 1100 in 3 in. models. I have gotten in many arguments with people cause the insist that his guns are the 11-87 because they fire 3 in. shells. But they are both 1100's and fire any 2 3/4 and 3 in. shells we can put in it.