Pretty sure in 1985 most of the US Army still used the M16A1 as their primary rifle. And the M16A1E1 was a transitional prototype for what would become the A2. The ingame model doesn't even feature a glued-on brass deflector on the upper receiver, although..these are known to fall off the rifle after some use so i suppose that's fine. But did the A1E1 not feature the A2's rear sighting?