As Juna said, they would probably have amnesty turn-ins for a set period of time and then after that you'd be committing a crime by possessing one. Depending on how deep your JBT thug fantasies run, it could be anything from going door to door with metal detectors or like the
story floating around of having your family do the right thing and turn you in.
Frankly, I can't imagine a bill without some sort of grandfather clause passing. I wouldn't lose sleep over grandfather clauses.
Look, people were saying that there would be an AWB/.50 caliber ban/total gun ban the second Pelosi walked through the door. Some were saying by the end of January. While there has been some gun legislation introduced, it has been sent to committee and none of it even approached any kind of sweeping. While there is no doubt something will be proposed, none of us know when or how exactly things are going to go down. I know that a lot of gun owners seem to experience some kind of thrill through constantly fretting about "the ban" on the internet for some inexplicible reason. If you are really concerned about it, get involved now. Join the appropriate organizations, take someone new shooting, write your letters, and vote. All the hand-wringing on the internet isn't going to make a lick of difference when it comes down to it.
I simply refuse to live my life in fear that someone is going to come and take my guns. I think I do my part. I encourage others to do theirs. Most of all, I enjoy what I have today. It is one thing to be aware of what is going on around you and in the world. It is another thing altogether to worry day to day that they are coming for you. If that is how you live, you've already traded in your freedom.
Don't get me wrong, if you really want something that might be banned, by all means, make a plan to get it. But if you do get it, take the time to enjoy it. Don't stash it away worrying about when the bad men are coming for it.
If you are worried about a ban and trying to decide between an AR-15 type rifle and handguns, I would go for the AR-15 first. Pistols with hi-cap magazines might be an issue, but that depends on the pistol. I would guess that if you were interested in a revolver or shotgun, those would be nearer to bottom of the list in the steps to a total ban.
You may want to disregard everything I've said as someone will be by shortly to declare that I'm some kind of ignorant blissninny that can't see the writing on the wall and that we are all doomed.