This new law is going to be a pain for hunters and shooters.
California Proposition 63 was written to force individuals who wish to purchase ammunition to first obtain a four-year permit from the California Department of Justice. The ballot measure requires dealers to check this permit before selling ammunition. California enacted legislation in July 2016 that repealed this provision and instead mandated dealers to check with the Department of Justice to determine if the buyer is authorized to purchase. The background checks requirement will take effect on July 1, 2019.
Proposition 63 also requires individuals and businesses to obtain a one-year license from the California Department of Justice to sell ammunition. Hunters selling 50 rounds or less of ammunition per month for hunting trips were not required to obtain a license. You can read the full text here.
The penalty for buy or selling ammo without a background check or license is a misdemeanor. As a result of this law ammo sales have skyrocketed in California. According to some sources ammo sales are up 300% since the law passed.
This video explains how the law will affect buyers
Before long maybe only airguns will be legal in California