Originally Posted by Drew Hause
Geoff: your gun was proved twice, and I believe the Birmingham date code is a 'M'
Argo's point is that in the absence of a shot mark the original London proof is 1887-1896.
The problem is that some early proof marks are lost or marked over with later re-proof

Lloyd's gun was proved 3 times, and the Birmingham date code is pretty clearly a 'T'

Thank you.