The 338 Ruger Compact Magnum (RCM) was introduced in 2008 as a companion introduction to the 300 RCM. A joint project between Ruger and Hornady, the RCMs are based on the 375 Ruger case shortened to 2.015-inch, enabling them to be housed in a short (308 Winchester) action. The 338 RCM's unbelted case has a rim and base diameter are .532-inch, same as standard belted magnums. This allows simplified manufacturing and generally smooth feeding, yet increases powder capacity over belted magnums of similar length. The 338 RCM is an efficient and powerful cartridge suitable for elk, moose, and big bears. Factory loads deliver 2850 feet per second with a 200-grain bullet and 2710 fps with a 225-grain bullet. So far Ruger has been the primary source for rifles and Hornady the primary source for ammunition.
