seriously OP, this guy has it right. you have to push your limits.
-Caliber considerations/Rostering Guns:
It is outrageously expensive to get off-roster guns and then your mag cap is limited anyways. If you can get a Glock 30 or 17 you can pretty much get the best you can in California.
2. Long Gun (Shotgun)
-Pump vs. Semi Auto
Honestly, it's whatever action you feel the most confident in. I go with Pump because you never know how little power a shell might have and you need at least 1 oz of shot or a projectile to assure that the firearm cycles
Classic Remington vs. Mossberg (Ford vs. Chevy, blah blah). You can have an endless fight about this. Just get the one with the most aftermarket support and the possibility for the largest magazine capacity.
AR-15/AKs are useless in California unless they are "featureless". I have a Saiga Sporter in 7.62 x 39. That's the best you can do for an AK in California. A featureless rifle means that you don't need a "bullet-button" to classify it as a fixed-magazine firearm. In that regard featureless rifles are actually functional.
The king three are the Saiga Sporter, Vepr, Mini 14/30