|Place of origin United Kingdom|
Case type Rimless, bottleneck
The .242 Rimless Nitro Express, initially called the .242 Manton was a rimless bottleneck centerfire rifle cartridge developed by Kynoch for J. Manton & Co of Calcutta and introduced in 1923.
The .242 Rimless is very similar to the .243 Winchester in performance, although the cartridge is significantly longer. It fired a 100 gr projectile at 2800 fps.