Casting or Forging Marks ??

[jamese]

Thought I would post the question maybe some knowledgeable people can shed some light

About a year ago I purchased a S&W M/P 15 AR . I never got a chance to shoot it much because my son always wanted to use it when we went shooting

Last month I decided to build an AR for my son and ordered a kit from Double Star. While cleaning the guns the other day I noticed that both guns had the same upside down U shape casting or forging marks on the upper.

Are both of these uppers made by the same manufacture???

S&W M/P15


Double Star



Any Thoughts from the folks that know alot more than I

Jim

[jamese]

Tac,
Your correct it is a Keyhole, but its raised , not stamped into the metal. iIts part of the casting

I raised this question on another forum also, and was told in fact it was casting marks and the codes are as follows for those interested.

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

Jim

[John Sabato]

Jim,

You probably already use this forum, AR15.com, but if you don't, you should be able to find any information you need there on this gun.