model 550-1 ser no and front sight hight

[John Gyde]

The B11 is not a serial #. The 550s were not given serial #s until 1968 (actually Oct 1967). The "B" probably stands for January and is part of the date of assembly code. You need to look at the "11" again. It is probably lightly struck and on close examination should give you the year of assembly (production). Check the RSA home page for the code.

[John Gyde]

Good photo! It sure looks like B11. I have no idea as to the date....

[John Gyde]

The DE3 means that it was returned for factory repair in September 1958. Letters followed by a "3" indicate a factory repair.