Looking for any information that you might have regarding some marks on a set of English made Wm. Moore & Co. barrels. The barrels belong to a side lever hammer gun (non-rebounding back action locks), estimating 1870’s vintage?

[Linked Image from i.ibb.co]

The mark between the “J & M” is a six pointed star.
“E.J. F10”? Any clue as to what that means?