Design cartridge length is 3.500". Will fit a Classic Post 64 M70, the Montana M99 long actions, Mark X Mauser with magazine box modifications, M98 Mauser with new bottom metal and rail/action work plus opening the magazine well to the rear. And of course the custom actions like Hein, Harre, Johannson, etc.

Depending on the bullet, and cannulure placement, etc., you can run the cartridge length up to 3.6" or 3.65" or so if the action and magazine are suitable. I am thinking of Northfork bullets here or some of the longer mono metal bullets.