Official caption: “A sniper of the 5th Battalion, 2nd Marine Brigade (ROK) uses a scope to draw a bead on a Viet Cong during Operation Dragon Five, Oct. 22, 1967. The operation is taking place on the Batangan Peninsula, South of the Chu Lai Marine Air Base.”
Of interest in the above photo, besides the fact that he has a horrible cheek weld and the dust cover is closed, is the ROK Marine’s early M16, equipped with a non-standard low-powered optic.
While Colt marketed the Dutch 3x25mm Delft scope on 601 model AR-15s in the 1960s– before they marketed their own 4×24 optic, the above is neither of those. The ROK’s optic looks sort of like a basic Weaver commercial scope of the time.
I’ve also seen another non-standard optic, possibly a Redfield, in at least anecdotal use with an M-16 in Vietnam:
If anyone knows more, drop me a comment or email and I’ll be most appreciative. Watch this space for updates.