This Beretta Optics Mount is not compatible with APX Carry model pistols. You would need to purchase the APX Carry specific optic adapter plates which include mounting options for the C-More, Shield RMSc, and Holosun K footprints. These plates can be purchased directly from Beretta, and can be found by using the link below:
https://www.beretta.com/en-us/gun-accessories/handguns/kits-parts/beretta-apx-a1-carry-optic-plate-c-more/