AR-15 Upper Receiver Forge Markings:
A (Splintered) = Anchor Harvey Aluminum
AF = Alcoa Forge
C AF = Colt Alco Forge
C MB = Colt / Mueller Brass
Cardinal (Stylized) = Cardinal Forge
CH = Colt Harvey Aluminum
Circle/Crosshairs w/ “AR” = ArmaLite
CK = Colt / Kaiser Aluminum
CM = Colt / Martin Marietta
D (Stylized) = Diemaco
DK = Diemaco / Kaiser Aluminum
E = Emco
EK = EMCO / Kaiser
E MB = EMCO / Mueller Brass
F Keyhole = FNMI / Cerro Forge
FA = FNMI / Anchor Harvey
FK = FNMI / Kaiser Aluminum
FM = FN/Martin Marietta
FMB = FNMI / Mueller Brass
Keyhole = Cerro Forge
L = Lewis Machine & Tool
LK = LAR / Kaiser Aluminum
LM = LAR / Martin Marietta
M (Under Diamond) = Mueller Industries
PA = Capco / Anchor Harvey
PM = Capco / Martin Marietta
Square = Brass Aluminum Forging Enterprises
The two most popular symbols you will see on AR uppers are the ‘Keyhole’ (Cerro Forge) and the ‘Square’ (Brass Aluminum Forging Enterprises), but you will see more if you keep your eyes open.
A (Splintered) = Anchor Harvey Aluminum
AF = Alcoa Forge
C AF = Colt Alco Forge
C MB = Colt / Mueller Brass
Cardinal (Stylized) = Cardinal Forge
CH = Colt Harvey Aluminum
Circle/Crosshairs w/ “AR” = ArmaLite
CK = Colt / Kaiser Aluminum
CM = Colt / Martin Marietta
D (Stylized) = Diemaco
DK = Diemaco / Kaiser Aluminum
E = Emco
EK = EMCO / Kaiser
E MB = EMCO / Mueller Brass
F Keyhole = FNMI / Cerro Forge
FA = FNMI / Anchor Harvey
FK = FNMI / Kaiser Aluminum
FM = FN/Martin Marietta
FMB = FNMI / Mueller Brass
Keyhole = Cerro Forge
L = Lewis Machine & Tool
LK = LAR / Kaiser Aluminum
LM = LAR / Martin Marietta
M (Under Diamond) = Mueller Industries
PA = Capco / Anchor Harvey
PM = Capco / Martin Marietta
Square = Brass Aluminum Forging Enterprises
The two most popular symbols you will see on AR uppers are the ‘Keyhole’ (Cerro Forge) and the ‘Square’ (Brass Aluminum Forging Enterprises), but you will see more if you keep your eyes open.
