You won't find much stamping on a 5.56 NATO round other than the circled cross (means it meets NATO specs) and maybe a couple of letters.
(LC means it was made at Lake City Army Ammunition plant. the 1 & 3 is a date manufactured. The other marks [dots] are SCAMP markings..denoting which machine and station made that lot) Small Caliber Ammunition Modernization Program. There is a little formula for decoding the SCAMP markings.
NATO rounds don't need much info on the casing, as each round was intended to be fired just one time and not to be reloaded by non-NATO approved personnel. (yeah, I know, lots of civilians do reload surplus NATO casings)
Some of Remington's .223 may say REM and some does not.
[This message has been edited by maryjane (edited 11-21-2020).]