Originally Posted by 375whelenIMP
The sight is an Armstrong also a later addition. Sedgley did catalog a magnum Mauser but I don't think this has any thing to do with that.

If you have a copy of Nick Strobel's book "Old Gunsights", you can see that the sight is a Redfield 100-M, production began in the late 1920's and ended in 1952.