"Redfield's were even selected for the Vietnam era sniper rifles." Horseman you're right.
I was a US Army trained sniper during the Vietnam War and carried what was then the XM21 (X designation for experimental weapons system) and now known as the M21. The daylight scope was a Redfield 3-9 power with an ART camming device on the variable power adjustment ring. They were a decent scope for their day.
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