Just purchased a BSA Cadet from here and was trying to establish the wording on the top of the Barrel

The Birmingham Small Arms Co Ltd
Cadet (BSA Logo) 1.77 ? and then what looks like GR **
Made In England

If I am correct the serial number (B61905) relates to production between1946-48.

Any ideas what comes after the BSA Logo, or am I just imagining things ?

Any advice greatfully received.
thanks
andy