According to The Fresno Bee:

More people are licensed to carry concealed weapons in Fresno County than any other county in California, according to data from the Fresno County Sheriff’s Office and the Fresno Police Department [17,400 licenses for a population of 994,000].

And

Orange County is next with 12,008 licenses [population 3.2 million].

And

Los Angeles County, with a population of more than 10 million, had only 424 permits as of last summer….

And

San Diego County [population 3.3 million] had fewer than 1,150, and Alameda County [population 1.7 million] had 186. The fewest licenses were reported in San Francisco County [population 883,000], where the state bureau reported that there were only two CCW licenses….

On the other hand, here are the homicide rates (2018 figures) for those counties:

Fresno County: 5.3 per 100,000

Orange County: 1.5 per 100,000

Los Angeles County: 5.5 per 100,000

San Diego County: 2.5 per 100,000

Alameda County: 5.5 per 100,000

San Francisco County: 5.3 per 100,000

High legal gun ownership doesn’t seem correlated at all with high homicide rates.  Quite the opposite: the trend is fewer killings as gun ownership increases.