I have recently discovered these forums and in turn, being the tech junkie I am, I am researching what I have and where it's made. I have seen various forge markings on uppers and wanted to see who knows what about who made them, etc.
"A" or kind of "A" shape cut in half forge mark on right side of upper
Keyhole forge mark on right side of upper
M on the front of the upper above the gas tube hole(was told it was an "FN contract upper)
Makers of Rock River Arms uppers (no markings, previous to the RRA marked uppers)
Please feel free to add any not listed above.