Excellent, we're getting somewhere!

Thanks for the comparison Roger, that's very helpful. I do feel that this rifle was reconfigured in the UKicon post War at some stage, certainly for civilian purposes. Might be an individual, might be a club, might be a school, no idea.

I'll accept the flaming bomb, was not contentious, and AdE's comment is bang on the mark, thanks Alan.

The confusing things still is the absence of the US Property stamp. Was this ground off, was it such a good and careful job, was the stamping so light or crude in the first place that it made it easy for the smith to do some touch up work to make the rifle gleam? Who knows?

Great input, thanks folks, appreciate the effort. Let's hope some one will wander by and recognise the receiver ring stamp mark.