Great looking Revolver Geoff, it's a classic
British design icon, like the Spitfire, Mini or a route Master bus.
I've had a few over the years Geoff, finish wise (I will dig out the pics) they seem to go from a deep Matt blue to a sort of parkerised / oil type flat dark grey.
I always assumed the park "type" grey was later in the great war when perhaps the pressure of production led to a more basic finish.
If you wanted to shoot it Geoff, would you have to put it on Sec7.3 ? Is that possible with .455?