Sergei Ivanovich Mosin (Russian: ?????´? ???´????? ??´???, April 2 or 14, 1849 - February 8, 1902) was a Russian Major General, engineer, and the main contributor to the design of the 3-line rifle, Model 1891 (Russian: "???????????? ???????? ??????? 1891 ????"), colloquially known as Mosin–Nagant.