A rotary ammunition magazine for a rifle has a follower that is spring biased and rotates about an axis to move cartridges for feeding to the rifle's chamber. The follower has a surface portion which engages the last cartridge in the stack. The surface portion has one or more characteristics including a transverse orientation angle, a longitudinal orientation angle and an arcuate shape which determine the direction of the force vector and the lengthwise load distribution on the cartridge.