Which riffle on which SIG SG 550 is based is a 5.56×45mm NATO assault rifle developed in the early 1970s by Schweizerische Industrie Gesellschaft?
SIG SG 540 The SG 540 is a 5.56×45mm NATO assault rifle developed in the early 1970s by Schweizerische Industrie Gesellschaft (SIG, currently SAN Swiss Arms AG) based out of Neuhausen, Switzerland as a private venture primarily destined for export markets and as a potential replacement for the 7.5×55mm Swiss SG 510 automatic rifle known as the Stgw 57 in Swiss service.
Mannlicher M1895 The Mannlicher M1895 (German: "Infanterie Repetier-Gewehr M.95" , Hungarian: "Gyalogsági Ismétlő Puska M95" ; "Infantry Repeating-Rifle M95") is a bolt-action rifle, designed by Ferdinand Ritter von Mannlicher that used a refined version of his revolutionary straight-pull action bolt, much like the Mannlicher M1890 carbine. It was nicknamed the "Ruck-Zu(rü)ck" (German slang for "back and forth") by Austrian troops and "Ta-Pum" by Italian troops who even wrote a song about it during World War I.