The SIG 530 was a Swiss assault rifle developed in the 1960s by Schweizerische Industrie Gesellschaft (SIG) to take the then-new 5.56x45mm NATO round.
Development of the rifle started in 1963 as a joint project between SIG and Beretta. The latter had already cooperated with SIG on the production of the SG 510-4 rifle for Chile. Initial prototypes of the 5.56mm rifle used the delayed-blowback operating system of the SG 510. However, this operating system proved to be problematic with the relatively "weak" 5.56x45mm intermediate cartridge, and the designers were forced to use a gas-operated, roller-locked system. In 1968, Beretta ceased development with SIG, and went to work on their own 5.56mm rifle design resulting in the outwardly similar AR70. Due to a lack of sales, SIG abandoned the SG 530 in the 1970s in favor of developing the SG 540 series.
- Hogg, Ian V. and Weeks, John S. Military Small Arms of the 20th Century. Iola, WI, 7th edition, 2000. Pages 280-281. ISBN 0-87341-824-7.