In one word: NO!
Factory primer pockets are swaged to final size, not cut.
Homemade re-cutting of primer pockets even when using a lathe and proper size reamers, is almost a guarantee for primer leaks. In a large high-pressure cartridge such as the S&W .500 that would be a DISASTER.
Proper re-sizing of your primer pockets would require both reaming undersize, and then swaging to final size. The special tooling needed would be prohibitively expensive for a hundred cases.
HTH
John