The Weaver story includes many hallmarks. Between the original K4 exposed adjustment, non-centered reticule in 1947 and the Steel Lite II version with Micro trac available from 1978-1984, there were many attempts to improve the scope itself, and the manufacturing process. That said, the K4 had many renditions through its reign. It was the most popular and is still the most famous hunting scope ever made. No other scope topped more rifles during that period. The Weaver Model K4 series was manufactured from 1947 until the close of business in 1984.
