CA-approved Glocks vs "regular" Glocks...
Is there any difference between a Glock 19 sold in, say Mississippi, and one sold in CA? Other than the CA gun coming with 10 round mags I mean? Basically, if I have 15 round mags already, could I buy a CA-approved Glock 19 and use my 15 round mags with it? Presuming it is legal for me to have those 15 round mags to begin with, which it is here in MS.
Go to California Dept. of Justice website...
If you go to the CA Dept. of Justice website and look under firearm frequently asked questions:
CA DOJ website FAQ
you will see this information regarding high capacity magazines in CA:
If I have a large-capacity magazine, do I need to get rid of it?
Note especially that "possession" of said magazines is not listed in the phrase "illegal to buy, manufacture, import, keep for sale, expose for sale, give or lend".
No. Continued possession of large-capacity magazines (able to accept more than 10 rounds) that you owned in California before January 1, 2000, is not prohibited. However as of January 1, 2000, it is illegal to buy, manufacture, import, keep for sale, expose for sale, give or lend any large-capacity magazine in California except by law enforcement agencies, California peace officers, or licensed dealers.
(PC Section 12020 (b)(19-29))