I was curious about markings on my upper, so did some research.
This is what i found.  I didnt know if anyone else could use it or not.




Forging marks   >  makers.

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

CK = Colt / Kaiser Aluminum

Circle/Crooshairs w/"AR" = ArmaLite

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



link to sight i found info on   http://www.armyparatrooper.org/dropzone/showthread.php/20426-Forging-marks-on-the-AR15-M16-M4-Upper-Receiver

You forgot...

JNK=JUNK

...like the one I bought at the Phoenix SAR show last month

Square box = Brass Aluminum Forgings Inc. ( found on Colt/Stag/CMT upper flatops and removable carry handles)....Mike. see correction below.

Brass Aluminum Forging Enterprises, actually.  It is often mentioned only with the acronym of their name, BAFE, and losing the "enterprises" would make the acronym not work...  Nice company in Ferndale, Michigan.

This doesn't seem to fit any of the above.
These are from a Barrett upper.  Best photos I could get from a not very good camera.
If I had to describe it, I'd call it a foot stepping on a piece of bread.

Any clues?

Cool to know. I bought a used A1 upper a few months back with no idea where it was from. Only that it was used, and still had the rear sight.

That's a Cardinal Forge.

tag

Thanks for the answer.  I never would have figured that one out.

The folks at Cardinal may think it's a stylized bird's head, but to me it still looks like a foot stepping on a piece of bread.

Opps:  I thought something was wrong.  I added the Inc. as I couldn't remember Enterprises.  Thanks for the correct.....Mike

I have one Delton upper with this forge mark. Who would have ever thought my Delton and Colt have so much in common.

Oh, and my new RRA too!  Who'da thunk it????

I know most board members hate Blackthorne, but they use the uppers with the square box forge marks=Brass Aluminum Forging Enterprises, as well.  First hand experience with photos if I have to.

Keep in mind regardless of  the forge mark, the company buying and reselling them is in charge of finishing machining and tolerance spec. So just because Blackthorne uses an upper with a quality forging doesn't mean they didn't do something to fuck it up after the fact.

Good example of this is RRA is known for super super tight tolerances, to the point of incompatibility with other companies specs sometimes.

Forge code only tells you where it came from in the beginning.

+1

Party pooper. lol

Mueller Brass?