Hi all,
  I'm new to the board here, and I don't have an AR-15 yet.  I am signing up with the Marines (OCC) and will probably leave this summer.  I live in CA, and therefore cannot legally buy AR's here.  Now, If I were to stop in...say Arizona, on my way to Quantico, would it be legal to purchase an AR-15?  Would I have to wait until I got to Virginia and am able to establish residency? (That would be after OCC.)
  Thanks for the help!
CB

Forget buying an AR in Arizona.  With the current California law, I believe that you could get in Federal trouble.

Assuming you are going to the OCS course with commissioning at the end, followed by The Basic School, then your specialty school, you should wait until you get to Virginia  and establish residency.

Sometime during the first week, you will be issued an M16A2.  You'll get a different one at TBS.  If you bring any weapons with you, they will be stored in the armory at OCS. I'm not sure about TBS.  I waited until I was enroute to Pensacola before picking up my guns from home.  Don't try to keep guns in your car or keep quiet about them.  Bad idea.  If you return to California after buying an AR out of state, you can't bring it with you.  Considering all the toys you will have access to for at least the first 9 months in the Marine Corps, you may wish to wait to see where they are going to send you before you make a major purchase.

By the way, your Dad wasn't a Huey pilot once upon a time, was he?

Thanks Dave,
 Now that I think about it more, your right.  I would have to be a resident before I could purchase a firearm, especially coming from CA. Not a big deal.  As you say, they'll issue me one, and It'll allow me to put away the paychecks so that I can get just what I want. (Man, a Pre-Ban Bushy-Dissipator would be nice, but I probably wouldn't have the money by the time I left unless I weasled some signing bonus or something, and I'm doubtful that the Marines are likely to provide that.)  We'll see.
  Nope, Dad wasn't in the Military. I'll be the first since my grandfather, a veteran of Korea.
I have an appointment with the Officer recruiter on Monday, and I'll be asking many questions, then a while to ponder on that info, but I'll probably be signing soon.
  Do you have any experience with Marine OCS? (I have some friends who went through it, but they're from work, and I don't really want to advertise that I'm gonna leave yet!).  Anyway, thanks forthe response,
CB

Chico Bill,
It all depends on where your ultimate duty station is going to be.
As a Kalifornia Rezident you can not buy an AR15 "while on your way out the door of Kalifornia" (unless you buy it private party, then who will know).
When you get to your ultimate duty station (if it's not Kalifornia) then you can buy anything that is legal in that state. I was considered a Kalifornia rezident while I lived in Oklahoma (Kalifornia dl), all I had to do was show a copy of my PCS orders and I could buy whatever I wanted.
If you do get stationed outside
of Kalifornia and then you get orders back to Kalifornia you CAN bring back your "evil" AR15's back with you, the catch is that you have to store them on base in the armory. They can never leave the base though. If you get out of the military then you will have to dispose of them IAW the current unconstitutional Kalifornia laws if you stay in Kalifornia.
I had a letter from the CAG/DOJ stating that this was acceptable, however, one Navy base I was looking at getting orders to had a CO who would not allow me to keep an
"unlawful" Kalifornia banned weapon on base, another base CO told me it was a-ok with him as long as it was in writing.
Something about Officers and their home of record sticks out, I can't remember if officers can or can't change their state of record (an enlisted person can everytime they re-enlist).
Good luck with your new career!

GEF