Quote Originally Posted by 5thBatt View Post
The change of the GR proof must have been later than 1940, both of these have 1941 dated receivers.
https://www.milsurps.com/images/impo.../B69002c-1.jpg
https://www.milsurps.com/images/impo.../B68727e-1.jpg
What S/N prefix have they got? I have two 41's with a D prefix and both have the later type Proof.