A word on hand gun safety.
First of all, let me say I don't like guns. I would like to see all of them dropped into the ocean. But this Pandora box, was opened a very long time ago. They are a reality. Being an American, I have felt that I should have one around for home defense.
The problem for me, was that I had 3 kids. (grown now). If you lock your firearm away, in a safe. You might as well have saved the money you spent on it. Odd,s are, by the time you dig the thing out. What ever you needed it for, is over.
My solution for this problem, was a the 1911 Colt auto. I found that my children could not work the slide, due to the stiffness of the return spring. By the time they were big enough to work it, They had been well trained in gun safety. I would test this with them from time to time. By handing them a very, very carefully unloaded weapon, and having them try to work the slide back. When they reached an age where they could do it (about 12 years old) They received a lecture, that lasted about a week, on gun safety.
I dismissed the choice of revolvers out of hand. Most don't have a safety of any kind. and are point and shoot affairs.
Another advantage of the .45 cal. APC. Is that it is a fat, slow moving, slug. Its not going to go through 3 walls and, kill the guy next doors cat, like a magnum might. Yet it is a proven cartridge, having been used successfully, in combat, thousands of times over decades.
There is no perfect solution, of course. But, a loaded, unchambered, .45 is the best one I could come up with.