Hi Ar'ers!
I just purchased a new (to me) AR Upper. It is a flat top and has "T" numbers on it that are black. I believe the Laser engraved T numbers. It has no distinguishing marks or anything anywhere on it except a small symbol on the side of the reciever just above the forward assist where the assist comes to a point and blends into the upper. The mark looks like an R except the top of it is round with a dot in the middle of it and the bottom is slanted both ways with a dot in it. I assume it's a symbol of a steel hooded ramp and peep. The reason I need to identify this is because I need to know if it's chambered in .223 or 5.56. There are no stamps, marks or numbers that I can find anywhere on the upper. I can take a picture and post it if need be. I can say the berrel is either stainless or chrome on the inside and the twist is 1x9". The barrel length is 20" and the forward assist is round and not tear drop.

Thanks in advance for any help you are able to provide.

Brian

I Just measured the Barrel and it measures .875" under the handguards and .725" within an inch of the muzzle. The finish is an exact match to my bushy and darker than a RRA with a 4 digit serial number.
Here is a picture of the upper with the only distinguishing mark on it:

http://members.cox.net/black_heart/Upper.jpg

From what you describe, it is impossible to know what the chambering is, since you apparently don't know who made the barrel.  A totally unmarked barrel is just that---totally unmarked

If you can, I'd suggest getting back to whomever you bought the thing from, and asking him/them.  The marking on the upper is simply the ID of the forge that turned out the raw blank, and tells you nothing about the brand of the upper, since all the manufacturers are using the same two or three forges.

I purchased this from the Equipment Exchange on here. The guy selling it had purchased it from soneone else on the Equipment Exchange as well and sold it because the color was darker than his lower. I would think that the laster engraved "T" Numbers would at least narrow it down. I know bushy chambers all of their AR's in 5.56.

Black Heart! Are you wanting to know if this upper is chambered in a non standard calibre? You do know .223 and 5.56 are the same thing right? I have never seen a non-marked non standard barrel before.

Quoted: Black Heart! Are you wanting to know if this upper is chambered in a non standard calibre? You do know .223 and 5.56 are the same thing right? I have never seen a non-marked non standard barrel before.

.223 and 5.56 chambers are not the same!  Without barrel markings it would be hard to determine which one it is.

As for the T numbers, if they were laser etched they would be white I think, it sounds like yours are machined into the receiver?

Quoted: Black Heart! Are you wanting to know if this upper is chambered in a non standard calibre? You do know .223 and 5.56 are the same thing right?

No they are not.

Long time listener, first time caller.  I have the same receiver that is mentioned, with no barrel markings also.  I got mine from Model-1.  This is the same receiver mark that has been on almost all of their receivers for the past three years.  All they will seem to say to me is "we cannot disclose the manufacturer of the uppers, only that they are a leading AR manufacturer."  I have seen, though, the same keyhole markings in DPMS catalogs.

Thanks
David
P.S.  How many of you guys here are from Tennessee?

These T numbers are very thin and coated in the same coating the rest of the receiver is coated with. It's not like the larger white T numbers I've seen pictures of. I guess I could pull off the scope and take a picture of the T numbers if you think it will help.

No I wasn't wanting to know if it was chambered in a non standard. I was hoping to find out if it was either .223 or 5.56 because they are NOT the same. I know it's either .223 or 5.56 but I don't know which. It's a safe assumption that I can shoot .223 but without knowing for sure, I can't shoot 5.56 because of the greater preasure of that round.

Thanks Dave!
I know that Olympic Arms makes a lot of "Major Parts" for other companies. I am sure there are other companies who make Uppers for other companies as well. I'll bet it is a Major Brand that's been left unmarked for re-sale if what you say is true. Do you know what DPMS's "Standard" chamber is? If not no biggie. I'll go to their site and poke around and see if I can find it. I would assume if it was a "Non-Standard" it would be marked on the barrel.

Thanks,
Brian

The keyhole marking is the logo of Cerro Forge. They made the raw forging. As to who did the machining and finish - you can't tell.

Edited to remove my mistake and to add:
There are at least seventeen North American companies that produce forgings for AR uppers.

Thanks for all the help. I know I can shoot .223 with it so I'll stick with that until I sell it, trade it or ware it out. It's a great shooting barrel who ever made it.

Brian