Those who say an unintended discharge of a handgun is always the handler's fault are wrong, and I can prove it. There can be, and have been, design defects which can cause, and have caused, an unintended discharge, sometimes with tragic consequences. This has happened with guns that were out in the general populace for years before the problems were discovered and corrected.
For example, I carried a US made (S&W) Walther PPK/S every day for several years that had a design driven defect which manifested itself as an unintended discharge happening when the decocker was moved from fire to safe while lowering the hammer. It never happened to me thank goodness, and Walther recalled and fixed them, but with my gun being in the critical serial number range it was pure luck that it didn't go off. I can't tell you how many times I racked the slide to load the chamber and then lowered the hammer using the decocker, which is exactly what it is for. Lowering the hammer any other way on that pistol, like by pulling the trigger and trying to lower it with your thumb, is unsafe practice. I may have been saved by the fact that I usually loaded, unloaded, and cleared the gun with the decocker in the safe position which met the hammer followed the slide forward. But it definitely could have happened.
If it can happen with a design as old as the Walther PPK series (production began in Germany in 1931 - S&W unknowingly manufacturered defective pistols for ~6 years), it can happen to any manufacturer. On that basis, the odds are that there are almost certainly more defects that can result in an unplanned discharge that haven't been discovered ... yet.
So, despite all the claims that ND's only happen to stooooooopid people and the guns are never, ever, at fault this condition is proof there may be ways for an unplanned discharge to happen even to a person paying very close attention to what they are doing if the gun has a built in defect the manufacturer hasn't announced yet. As in this example, the existence of the gun in the market for years is no guarantee that can't happen. I said "unplanned" on purpose because something like the US Made Walther design defect causing a discharge isn't a Negligent Discharge. There was no negligence on the part of the owner/handler, the gun discharged when it shouldn't have through no fault of the handler who was following proper procedure. This reemphasizes that muzzle control is important because if proper muzzle control is practiced and an unplanned discharge happens it will minimize the chance for personal injury or death.
Which brings me to my point.
What is under discussion here is the concept of a portable "guaranteed safe" place to point the muzzle while loading, unloading, or clearing the pistol. It doesn't seem like such a bad idea to me.
A 5 gallon bucket of sand with a normal plastic cover on it ought to do a decent job of stopping most handgun bullets but I've never tried it. I may do that just to see if it will. If it does I may put one in an out of the way place in my closet to use as a "bullet bucket". I've been lucky so far, but "luck" isn't a plan.
Fitch