As far as I know you can't thread your barrel in CA unless I'm misinformed they don't want you using flash hiders or silencers, the brakes for the 44s don't fit cause the front sights are slightly differnet I tried one and they are too loose and sag Down off the front of the barrel it's got to do with the bayonet, if someone knows for sure about the threading barrel thing in Cali please let me know where I can find out for sure, that's hat what I've always been told......so or those of you that don't live here...don't move here cause it sucks and if you do live here then RUN!! lol