P53 Barrel Stamping?

[milsurpshooter]

I'm not having having any luck in finding out the meaning of this stamp. My reference book doesn't show anything like it and the only online hit was a pic from an American Rifleman article back in the 90's. It almost looks like a fleur-de-lis. Anyone have any ideas?
Thanks,
- milsurpshooter

5145

5146

5147

[Smosin]

You might want to try posting that photo on the British Militaria Forum.
http://britishmilitariaforums.yuku.com/forums/4/British-Flint-and-Percussion-Arms#.WKB9ttIzWic