If you look closely...they all have something affixed to the barrel right in front of the forward sight. Too forward to be a PEQ box I think (at least I've never seen one placed that far forward)...but I'm wondering if it is some sort of training rifle.
looks like they are laser mounts and you can see the power cables in front of them. the pic of them in the prone position was the give away for simulators. the dude on the end is on a 249 saw, indoors, with no hearing protection. aint happening. :-)
It's not that you are ignorant, it's just that you know so much that isn't so.