I have seen it recently but the meaning has not 'stuck with me'.
I think it was something along the line of C in a circle was CanadianArsenals and was used on 7.62 Conversions.
Mine are not the best, but they are not too bad. I can think of lots of Enfields I'd rather have but instead of constantly striving for more, sometimes it's good to be satisfied with what one has...