I'm guessing the address.
Feel free to PM for engraving. :)
Printable View
300BLK is also known as the AAC 300 Blackout and 7.62x35mm.
http://300aacblackout.com/
I don't know of any requirements for the chambering to be marked on the receiver though.
What does it say on your AR?
If you're asking me -
Sorry, that was poorly phrased. I meant that there is no requirement for the maker to mark the caliber if there is already a marking indicating the caliber.
Actually if you are changing the caliber in primary designation you need to mark the reciever or the barrel with the caliber that is easily read. Since the barrel will be completely covered with foreend, then there it be.
Any gun manufactured, imported, or made on and after January 30, 2002 must have manufacturer information placed at a minimun depth of .003” with a height no smaller than 1/16”.
This information must be engraved, cast, stamped (impressed), or otherwise conspicuously placed on the frame, receiver, or barrel.
Required information on an SBR is the model (if such designation has been made), caliber or gauge, and the manufacturer’s name (or recognized abbreviation). Also for a domestically made (SBR) the city and state (or recognized abbreviation), where you as the manufacturer made the firearm.
Orion Arms did my sbr for $35 + $16 shipping. Front of magwell, 21 characters. looks great, very small text!