Having researched M14 military optics, here’s my 2cts. The 6x Nimrod scopes were introduced by the IDF in the "mid-1980s," and were used for about a decade. The original Wild Herrbrugg 4x scopes were used previously on M14s - from the mid-1970s to the mid-1980s. (Note: the Wild Herrbrugg 4x scopes were presumably removed from their old K98 rifles and installed on M14s in the early 1970s).
Here's the original IDF M14 scope on top (green painted 4x Wild Herbrugg) that was reportedly used from the mid-1970 thru mid-1980s, and below it is the replacement scope, the 6x40mm Nimrod, reportedly used from the mid-1980s until the mid-1990s. Turrets seem are M852 and M118, perhaps others.
And here's a picture of an early IDF M14 sniper with the original/1st iteration Wild Herrbrugg 4x scope. I suspect this picture might date to the 1983 invasion of Lebannon, but I can't be sure.
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Here’s an IDF M14 sniper with Nimrod 6x scope.
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The final IDF M14 sniper scope introduced in 1994, which was the Austrian made Kahles/Swarovski 'Futonic' 6x42mm scope. They are easily identifiable with a rather large rubber ocular cover that makes the scope look like it has much larger objective lens.
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