Frank, I don't know if you want this one, but I have a Mauser luger with a "42" chamber date s/n 715g that is military proofed E/135 with no barrel gauge mark and with no commercial proofs present. Manufactured in May, 1942.
Rather than a "byf", it has a Mauser banner toggle with matching number.
From recent comments by Joop on Jan Still's forum, he indicates that this was an uncommon (but known) variation as Mauser started using all available parts to fulfill the last German military contracts.
Marc
|