The Combat Magnum was the first K-frame to be made using a 4-screw frame. The directive to delete the upper side plate screw and other changes on K-frame revolvers was issued on September 7, 1955. The change for N-frame revolvers was issued a year later. Stamping of the model number was implemented for most models in 1958 even though the directive to do so was issued on June 12, 1957.

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