What is another name for the Barrett M82 based on it use of a cartridge that is the standard cartridge for NATO forces as well as many non-NATO countries?
Barrett M82:  It is also called the Light Fifty for its .50 BMG (12.7×99mm NATO) chambering and significantly lighter weight compared to previous applications. .50 BMG:  Under STANAG 4383, it is a standard cartridge for NATO forces as well as many non-NATO countries.
Light Fifty