So how many rounds can be fired continuously through a 5.56mm suppressor? Instead of using an AR why not use an M249 Light machine gun to quickly see the result. This is what this person is demonstrating in this fun gun video. Is there a purpose to all this? Probably nothing, Here's what some are saying: What we do know is that people (human behavior) are just amazed at the look of a fully glowing suppressor on an automatic machine gun. See the full suppressed M249 gun footage here.