If you didn't own 10+ magazines before the year 2000 and you're not a; LEO, military, or armored car employee (and given the magazines by the owner) then you cannot buy them. Possession isn't illegal, as long as you got them legally. Bringing any 10+ magazines in from another state is illegal, but bringing them in as parts is not. Make sure you do not assemble them in CA.
Here's something to remember though... Putting more then 10 rounds of a smaller caliber in a 10 round magazine made for a larger caliber is not illegal and you can buy as many of those as you would like... Use at your own discretion though because many people have enough problems with cops not knowing that OLLs are legal at all. You should own the upper that it goes along with too.
If you do own some legal "high capacity" magazines, or some of the magazines mentioned above you cannot use them in a bullet button equipped AR with evil features. It must be a featureless rifle which has the following features: non collapsible/folding stock (you can pin them though), no pistol grip (there are plenty of alternatives), no flash hider (compensators are ok).
Here's something to remember though... Putting more then 10 rounds of a smaller caliber in a 10 round magazine made for a larger caliber is not illegal and you can buy as many of those as you would like... Use at your own discretion though because many people have enough problems with cops not knowing that OLLs are legal at all. You should own the upper that it goes along with too.
If you do own some legal "high capacity" magazines, or some of the magazines mentioned above you cannot use them in a bullet button equipped AR with evil features. It must be a featureless rifle which has the following features: non collapsible/folding stock (you can pin them though), no pistol grip (there are plenty of alternatives), no flash hider (compensators are ok).
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