A couple of thoughts to help people on the side of gun control have a discussion that does not immediately get shut down. I sincerely hope this helps and nobody feels like I'm targeting them. (Charmin particularly since I'm responding to your post)
Here's the list of major firearm restriction legislation. Yeah, I pulled it from Wiki. Discussions have taken place. Concessions have been given by advocates in the past and no sign of "enough" has been seen. The problem, I think, that people who sincerely believe that more restrictions will actually have some kind of impact run into is that there have been swings in violent crime that all the legislation below had little if any discernible effect on. That's going to be a major hurdle in getting advocates to listen. You'll need to understand what all this legislation was first.
National Firearms Act ("NFA") (1934)
Federal Firearms Act of 1938 ("FFA")
Omnibus Crime Control and Safe Streets Act of 1968
Gun Control Act of 1968 ("GCA")
Firearm Owners Protection Act ("FOPA") (1986)
Undetectable Firearms Act (1988)
Gun-Free School Zones Act (1990)
Brady Handgun Violence Prevention Act (1993)
Federal Assault Weapons Ban (1994–2004)
Secondly, using terms like "common sense", "sensible", and the like is wholly condescending and most likely ends the conversation. Probably best to show respect for other people's opinions when saying that an adult conversation is necessary to someone who doesn't think that there is any need. This is a huge sticking point for advocates.
Third, if folks on the side of gun control really want to have this conversation, then they will also need to have a well versed understanding of all firearm types including functionality, past legislation, and the Federalist Papers interpretations of the 2A written by the Founders who penned the Amendments. Pretty much anyone that wants to lead a discussion about a topic that they are not well versed in gets ignored.
I think it is in the best interest of anyone wanting to advance the discussion to understand that the above are "pet peeves" of people that believe in firearm rights. If you are very passionate about your opinion I don't think it would be wild to ask that you research and understand all these points, but this is a LOT of reading. It is not unreasonable to ask that the discussion does not involve the speaker being educated by the audience. If you want to be listened to you will have to become an authority on the subject.
Then again, there are plenty of advocates that are just done giving inches when miles are the goal. They won't talk to you anyway.