You're right. I was trying to remember which we're open bolt vs closed and confused myself trying to draw the correlations. The M2 is closed bolt, ambidextrous fed, bottom ejecting but does not have a dust cover over the feeding port. But the bolt is closed below the feed port. I was just thinking a second ago. It's been 13 years since I was in the armory fondling these weapons and taking them to the range. They don't train on 60s, 249s and 240b's anymore in basic? Out of all of them though I will still pick up a m4 with a 203 any day. My favorite. Versatile, light, and will jack some stuff up. No such a thing as cover and concealment. He, Cs, flare, Ap incendiary, frag and oh, a rifle. Lol.