What would happen? WE WOULD MAKE MORE. Violence is inherent in determining power and hierarchy, and an intelligent species is always going to pursue the most effective technologies for inflicting violence and use those technologies to maintain a monopoly on violence, ie a government. Failure to do so just means someone else will come along and do it for you.
Guns are not the problem. Violence is inherent to the human condition, and to intelligent species more generally, because only beings willing to inflict violence when needed survive and reproduce. This is why gun control, in the modern sense, is so deranged. It fetishizes one manifestation of an ancient, atavistic urge while failing to understand that said urge runs much deeper than any given technology for inflicting it.
no matter what weapon there is no less horrible way to take life
Yes, we have a high murder rate, but other violent crime is lower than average--because the possibility of the victim being armed is a deterrent. Some years ago we had a burglar on our block, pretty obviously a local. Notably, every house that was hit was a place with nobody who appeared to have any combat capability and were people I would consider very unlikely to have a gun. Chance? I think not.
Huh... That's much lower than I expected. So all these decades of heated argumentation over this while car accidents kill 3x the number of people.
Also keep in mind that removing guns doesn't remove the intent to kill. Many of the people who intend to kill somebody will find a way without a gun.