A manufacturer is that person, company or enterprises that produces large numbers of goods through a manufacturing process in which raw materials are transformed into finished goods on the large...
The action of the rifle was made by Fabrique Nationale in Belgium, and was their basic commercial FN Mauser action. The actions were barrelled and completed by High Standard, hence the '583' model...
Armalite was the original manufacturer. Colt however, was contracted to supply the U.S Military with M16's during the Vietnam war. Also still to this day.