Originally Posted by cycloneman
Jump to 1959, the year Winchester introduced their very successful .22 Winchester Magnum Rimfire (WMR). This cartridge pushes the limits of pressure possible with a rimfire case given the limits of contemporary metallurgy. The .22 Magnum was initially offered with 40 grain FMJ and JHP bullets at an advertised MV of 2000 fps from a rifle barrel and 1550 fps from a pistol barrel. Due to its high velocity, .22 WMR cartridges are loaded with jacketed bullets.
Thank you for all of the imformation on rimfire .22's. Correct me if I'm wrong, but I understood that the the .22WMR was developed to achive .22 long rifle like ballistics in the then very popular Ruger Single Sixes and their clones.