The purpose is to make gun ownership as much of a hassle for Californians as humanly possible. Any “criteria” there may be are arbitrary. The SIG P320 isn't on the list because it's a popular gun that people want, and that's reason enough for California to ban it.
Is SIG P320 single or double action?
The P320, on the other hand, is a striker-fired handgun. Unlike all of the other handguns in the P220 series—which use either traditional double-action or double-action-only (DAO) triggers—the P320 has a short and consistent trigger pull with a short, positive reset.20 ene 2017
What is wrong with the Sig P320?
Slatowski's lawsuit argues that the P320 design "possessed an inadequate sear-striker connection, even after implementing a 'voluntary upgrade' program for the gun; an inadequate internal striker safety; and lacked any external safety or tabbed trigger safety," the lawsuit states.19 feb 2021
Is the Sig Sauer P320 x5 Legion legal in California?
The Sig P320 came out in 2014 so it can never be added to California's list unless that Microstamp Law gets repealed.