Some time in the 1950's Steyr Mannlicher Schoenauer (Steyr M/S) introduced their swing "away" scope mounts/rings. From my observation at least two series of these mounts were built for the "size two" (1 inch scope tubes). I have a series 1 swing mount of the size two on my 1952 Steyr M/S that was built for AKaH.

The series 1 design required filing/fitting of the rear mount to allow it to work and swing properly. This fitting issue was corrected in the subsequent series 2 swing mount/rings by changing the rear mount to factory milling of the "U" shaped slot from 90 degrees to the barrel bore to 85 degrees. Other changes to the rear mount were make to make it easier to release the scope to swing it away from the rear mount as well as to re-insert it. The front ring bottom was changed a bit, apparently to make it more rugged.

My question to the readers here: does anyone know what year the series 2 swing mount was introduced?

Kindest Regards;

Transvaal