The .308 Norma Magnum was superseded in popularity by a firearm that was released in what year?
.300 Winchester Magnum: The .300 Winchester Magnum (also known as .300 Win Mag or 300WM) (7.62×67mm) is a belted, bottlenecked magnum rifle cartridge that was introduced by Winchester Repeating Arms Company in 1963.
i don't know