If your domestic violence offense was a misdemeanor, after a 10 year waiting period, California will automatically restore your state gun rights.
Regardless of that, however, you're not home free. A misdemeanor crime of domestic violence not only costs your your state gun rights, but it will take away your Federal gun rights as well. Under the Violence against Women Act and the Lautenberg amendment, the bar against your Federal gun rights is for life.
You can see the Federal definition of a crime of domestic violence below. If your conviction doesn't take in those elements, you would still have your Federal gun rights, and you'd only have to concern yourself with California. But if the case for which you were convicted conforms to the Federal definition, there is nothing you are going to be able to do unless/until the law changes:
For purposes of its unlawful gun possession statute, the Federal government defines a misdemeanor crime of domestic violence in 18 USC 921. The statute says:
"the term misdemeanor crime of domestic violence means an offense that:
(i) is a misdemeanor under Federal, State, or Tribal law; and
(ii) has, as an element, the use or attempted use of physical force, or the threatened use of a deadly weapon, committed by a current or former spouse, parent or guardian of the victim, by a person with whom the victim shares a child in common, by a person who is cohabiting with or has cohabited with the victim as a spouse, parent, or guardian, or by a person similarly situated to a spouse, parent, or guardian of the victim."
Without Federal rights you risk Federal charges for being a felon in possession of a firearm and neither your California rights nor an expungement would protect you from Federal prosecution.
Without Federal rights, you will not clear a NICs check, nor will you be able to get a carry permit. The only thing that would restore your Federal rights would be a full and unconditional pardon, which is based on actual innocence and which would have to expressly restore your gun rights. So unfortunately, until Federal law changes, you're essentially without rights, even after 10 years.
I am sorry to be the bearer of bad news, but hope that I have clarified the law as to these types of misdemeanors.