I was just about ripping my HAIR out trying to figure out who manufactured all of the bolts i own and stumbled upon the information posted below. This is more for an FYI as it is a discussion. Hope this helps some of you out.
C - Colt
stylized D - Diemaco
F, FN - FNMI
“Y” in a circle = Olympic Arms
BCM = BCM
D - Amateec Arms
TC - Toolcraft (DPMS, Bushmaster) (cage 1B1B6)
CM - CMT
A - Advanced Ordnance Corp (CAGE 077H9)
Shield and SE - Smith Enterprises
M - Smith Enterprises (Marine Corp)
N - Smith Enterprises (Navy)
J - Smith Enterprise for JC manufacturing in the mid 1980's
TM in a circle - Young Machine
Y/M in an octagon - Young Machine
FA or AF (small A, large F) - Fulton Armory
C - Colt
stylized D - Diemaco
F, FN - FNMI
“Y” in a circle = Olympic Arms
BCM = BCM
D - Amateec Arms
TC - Toolcraft (DPMS, Bushmaster) (cage 1B1B6)
CM - CMT
A - Advanced Ordnance Corp (CAGE 077H9)
Shield and SE - Smith Enterprises
M - Smith Enterprises (Marine Corp)
N - Smith Enterprises (Navy)
J - Smith Enterprise for JC manufacturing in the mid 1980's
TM in a circle - Young Machine
Y/M in an octagon - Young Machine
FA or AF (small A, large F) - Fulton Armory