The .500/465 Nitro Express is a large bore centerfire rifle cartridge developed by Holland & Holland and introduced in 1907. The .500/465 Nitro Express is one of several rounds (including the .470 Nitro Express, .475 Nitro Express, .475 No. 2 Nitro Express and .476 Nitro Express) developed as a replacement for the .450 Nitro Express following the British Army 1907 ban of .450 caliber ammunition into India and the Sudan, all with comparable performance.
Holland & Holland created the .500/465 Nitro Express by necking down the .500 Nitro Express 3¼ in.
The .500/465 Nitro Express is designed for use in single-shot and double rifles.
