Yep you should have a bullet button on there . That meens you need a small pointed tool or a bullet to push the mag release . The stock should not be pinned . The bullet button allows people in CA to have all the other cool stuff flash hider , collapsible stocks , forward grips etc . Im not completely sure but I think the bullet button must be permanet to be legal . I believe that meens they use locktite or some other permanent thread lock . You will need to heat the bolt/nut up with a soldering iron to loosen the thead lock . Try to remove it with out heat first . I have a Del-Ton 316 for CA . I'll go see if mine is permanent .
EDIT : yep it has some type of thread lock on there . No way I can turn that little nut
. As for the gun it self I love mine It works very well and I been running it pretty hard as of late . I also used a Del-Ton upper to build an AR and it's working great as well . You did not make a bad choice . Maybe on the CA version but not on the gun it self .
Can you release the mag with just your finger ? if so you do not have the bullet button .