By A Mystery Man Writer
Bunch of newer odd headstamps - General Ammunition Discussion
Sleeping Giant Brass : 6.5 Creedmoor Federal Headstamp Large
Brass - Products
Can anyone identify this round? Head stamp has FC 223 REM. : r/guns
28 Nosler
Comprehensive list of brass case makers.
Headstamp - Wikipedia
Headstamp - Wikipedia
357 Magnum, Specialty Pistol Brass