Well, you have cherry picked a bunch of states that do have higher violent crime rates than California. But I don't see how much relevance that has. There are naturally other factors that influence and cause violent crime. My argument was that if more gun control works, then California should be doing better than it is.
If you compare California's overall rate with a more comparable sized state with far, far less gun control, such as Texas, you will see that California does have a slightly higher rate, instead of being lower.
Here in Oregon where I live, the violent crime rate is almost half that of California. Despite the fact that our gun laws are among the most lax in the nation, with instant background checks with no waiting periods, shall issue concealed carry, and even allow for full auto machine gun ownership.
Now Oregon is also over 90% Caucasian. Can one then infer that white people are less violent than minorities? I don't think so. There is only so much that one can infer from statistics.
I simply found it to be most ironic that in a state where merely the ownership of an AK-47 is now illegal, a criminal was walking around with one stuck inside his pants.
I lived in California for nearly 50 years and owned over 20 guns. If you want a gun in California, you can get one. The ability to own a gun has nothing to do with crime there. Any kind of gun can kill another, but if a small percentage of your population is capable of mass murder, you're still going to get more people in California capable of doing the same thing, as there are other factors coming into play here which would dramatically increase the possibilities.
California has a much higher urban population than Oregon. They have a higher indigent population, a higher population of addicts, a higher mentally ill population with a criminal propensity, a higher low income population, and higher non-gun crime rates such as car thefts. Much higher illegal population and more importantly a higher second generation population of low income hispanics more likely to belong to gangs in urban settings (while there are more illegals belonging to gangs today, the vast majority of hispanic gang members are US citizens, usually children of immigrants, legal and illegal).
Oregon's populatin is about
3.7 million. California's is roughly
10 times as much. Oregon has about 35 people per square mile, California has over 210. Natually, you will see more California murders in the media, just because of the shear number of the people there.
Many things cause more crime. Oregon has one large city, California has many of them. Rural residents will never commit as many crimes as urban ones.
One other thing most people don't seem to realize is that California, being more urban and probably anti-gun, will have more people not owning guns, who are afraid of them, even if they are available (and they are). Less gun ownership per capita means the thugs have an easier time commiting crime,
but it's due more to the mindset of the urban resident than the ability to own a gun.
I'm afraid your premise is a bit simplistic.
Time to revive the Federalist party of George Washington!!! 
) so they continue to use guns they get illegally.