A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.
Nothing in the constitution mentions registration one way or the other. I guess the question is whether registration represents an unreasonable infringement.
And yes, if you have not properly locked up your arms in a manner that prevents unauthorized use, you should be charged with a felony. (Not a slap on the wrist and small fine). A defense might be that a professional safe cracker was able to open the safe without your knowledge but not that you kept it in a cardboard box under your bed. My dad kept his rifles in a locked glass front cabinet. Kept us kids out but not burglars. That might have been ok in the 50s but not today. My brother keeps a handgun under the front seat of his truck. I asked him how he would feel if one of his grandkids got hold of it. He had no answer.
I pray that enough people get disgusted with the NRA's hardline "guns for all" stance that we can change the constitution. But how many more lives need to be ruined?