He's also a CCW permit holder in NYC, and his sons were raised to enjoy hunting game. Can't say how long he's been a member, but I've not seen any of those posed 'hunting' photos candidates like to flog around during election season, either.
If he was a phony on the issue, he would have been 'outed' by now. All I've seen is some 15-year old discussion about assault rifles, he was favoring some regulation at that time. I'll feel that is relevant when all the other GOP candidates give a speech to the American public stating they are against any regulation of assault rifles. They're not going to do that, and we all know it.