After proper research, I stand corrected. Hal Moore's men were carrying the XM16E1, a forward assist equipped AR15. It later became (1967) the M16A1.
Brian
Incidently, I do not commonly trust a lot of photos, especially if they come from the internet, as there is no control and no required provenance there. I have found photos listed as the USS ARIZONA, that were not even battleships.