[4][1][2] The "Los" was designed in early 1960s, the first rifles were made in 1961,[2] although serial production began since 1965.
[6] In the first half of the 1970s, experimental 9×53mmR cartridges with hollow bullet for immobilization of wild animals for "Los" rifle were made and tested.
[7] In 1993, Kazan Optical-Mechanical Plant began production of night-vision device for "Bars", "Los-4" and "Los-7" hunting rifles.
[9] The "Los" has staggered column non-detachable internal box magazine.
[2] All Soviet rifles had a wooden stock and fore-end,[2] although custom aftermarket variants are known.