i have seen many numbers and letters on Birmingham guns- i have never seen a list that details them -
this is one of mine- i guess TENT is a barrel maker - can't prove it
on this Greener - i have yet to figure out the marks on the under ribs
i have a feeling that barrel makers marks are most often initials not nnumbers
can't prove it - but based on guns and British reels, makers and inspectors are hard to pin down