Caliber Conversion
Unless otherwise specified, Beretta does not recommend converting a pistol (or any Beretta firearm) from its original factory configuration. Your pistol was proof tested as an assembly at the factory, after replacing the major components required to change calibers you would not be able to duplicate these safety inspections.
Naturally, conversion carries several risks, not the least of which is the safety of the shooter and surrounding people, but the warranty on the firearm, which is void following custom modifications.
Lastly, the cost of performing such a service would likely match or exceed the cost of a new firearm, making the purchase of a new pistol far more feasible