The first step in total gun control is a national data base. That is exactly what happened when I lived in NYC. I bought an HK91 when they were "allowed" and a year later I get a letter from the Firearms Control Board saying the HK91 is now considered illegal and I need to turn it in.
A friend of mine thought he could just ignore the letter and several weeks later 6 police officer knocked on his door and took his "assault" weapon away, a weapon that was bought legally until the same Senators and Congressman who are protected by fully automatic weapons decided citizens should not have guns. The same Senators and Congressman who have a total Health Plan ( a Health Plan that is complete with even dental and is passed down to the Senators/Congressman's children at our expense)that is not allowed for the common Joe. My friend was told he would have been arrested if the letter was send certified and the police could prove he signed for it and received it.The few people who can have a license to carry in NYC, like Donald Trump, are obviously more important than the ordinary Joe.
Once they know WHO owns a gun they can come for them. Right now it is assault weapons and semi-auto pistols but like England,France, etc they will come for all guns. It is just a matter of time.