My understanding is that the 50 AE uses the same diameter bullet as the 500 S&W; however, the 500 S&W can drive them to much higher velocities. The problem arises when people attempt to load lighter construction jacketed bullets designed for the 50 AE in the 500 S&W cartridge. As long as the velocities are kept reasonable (i.e., <1,600 fps), a coated bullet of this diameter should work in both the 500 S&W and the 50 AE.