Single shot, breech-loading, barrel over 16, no collapsible stock. The muzzle brake could be a problem, but it doesn't suppress flash much, so... The only problem here is that it's an NFA-regulated weapon, as it has a barrel over 50 caliber. That makes it a Destructive Device. That having been said, I hear it's actually possible to get DD permits here.     Yep, I think you can own one of these in California. But you have to get it with a micro-stamping firing pin, a fingerprint pad, and a safety lock. What you're naming off there is just for handguns. The fingerprint pad legislation hasn't been passed yet, however. They keep trying...