pnkssbtz,
no worries, if your looking into a SA M1A, they offer most of their models in CA compliant (ten round mag and muzzle brake) trim. Most retail shops in CA will be selling the CA versions of the rifles with ten round mags and muzzle break already installed. If you are looking at buying from an out of state FFL and having it shipped to a local CA FFL you better make sure that it doesn't have a flash suppressor/hider installed as that would make it an assault weapon (open mag well + flash hider). There are no laws that I am aware of (please correct me if I'm wrong) that prohibit threaded rifle barrels, so if you are insistant on buying from an out of state FFL, simply have him uninstall the flash hider before shipping, and install a muzzle break once you take possession (SA, and Smith come to mind for muzzle breaks), and buy some decent ten round mags.
jl1252