Did a bit of SEARCHING, but the search has limited duration. Found no stikies.

What are the manufacturer's codes (A for Alcoa, etc), and Where are they generally found. Have we an existing link? Is it already stickied?

TIA!

Stamping  Source  
CAF Colt / Alcoa Forge (See above for photo)
CH Colt / Harvey Aluminum (1st Colt Forgings)
CM Colt / Martin Marietta (See above for photos)
DK Diemaco / Kaiser
FK, FS, BK, DK, EK, FK, AF, CW, AA, FS Bushmaster
LK FN / Kaiser
LM LAR / Martin Marietta (Army Spares Contract)
Splintered A Olympic Arms

from the http://www.biggerhammer.net/ar15/uppers/   site

HTH

GoGo

MANY thanks!

Quoted: Stamping  Source   CAF Colt / Alcoa Forge (See above for photo) CH Colt / Harvey Aluminum (1st Colt Forgings) CM Colt / Martin Marietta (See above for photos) DK Diemaco / Kaiser FK, FS, BK, DK, EK, FK, AF, CW, AA, FS Bushmaster LK FN / Kaiser LM LAR / Martin Marietta (Army Spares Contract) Splintered A Olympic Arms from the http://www.biggerhammer.net/ar15/uppers/   site HTH GoGo

While biggerhammer's data is valuable, it is FAR, FAR out of date.  It does not include forging marks or uses like:

keyhole with dots = Cerro forge - used by RRA, Bushmaster, Colt and likely others
bird head symbol = Cardinal forge - used by ?
splintered "A" (mentioned above) = [slips my mind] - used by Bushmaster and seem on some Colt flat tops also
"AR" with a circle and cross in the circle = Armalite - used by Armalite (duh)
squiggly "D" = Diemaco (Canadian) - used by Diemaco AND Colt

There are likely others that I forgot about.

How about the NUMEROUS receivers out there with NO markings????  Who made those????

IMO, with today's receivers, unless it is a blatently obvious marking like Colts, Diemaco and Armalite, it is a pure crapshoot as to who actually finished that receiver.

Excellent additional info, although the biggerhammer info is JUST for forgings- there truly is no way to tell who does the machining- unless maybe we get into some serious forensics!  Yes, though you certainly find a mix and match going on.  Colt M4 uppers I've seen somtimes have Diemaco forgings for the carry handles, etc...

OK..........!!

what does a sideways heart with the bottom cut off mean ??

at least that is what it looks like to me.

Quoted: OK..........!! what does a sideways heart with the bottom cut off mean ?? at least that is what it looks like to me.

That may be the squiggly "D" that I was talking about.  I guess it would look like a sideways heart.  Diemaco.

thank you..., i never thought of it thata way, but you have given me a different way of looking at it !

The "splintered A" is actually an AH, for "Anchor Harvey", and every maker of ARs in the country is, or has, used them for forgings.

The Bigger Hammer website is great for info on early Colt stuff, not bad for later Colt info, and absolute garbage for anything else

C MB

(usually gray A2's)  Colt + ??

One more the Bigger Hammer list leaves out;  C K (Colt Kaiser), which I believe was confined to very late A1 and very early A2 production.