The SIG SG 510 (Sturmgewehr 57 in swiss service) is a battle rifle manufactured by SIGARMS (now SAN Swiss Arms) of Switzerland. It is based on the same roller-delayed blowback system used in the H&K G3 and CETME rifles. It is considered to be one of the most accurate mass-produced assault rifles available, and is very reliable in harsh climatic conditions. The StG 57 rifle (chambered for 7.5mm Swiss) was issued to the Swiss Army. Later the rifle was also offered for international sales, chambered in 7.62x51mm NATO as the SIG SG 510-4 but this variant has different external parts and was issued to the Armed Forces of Bolivia and Chile who still use it to this day in limited use.
