Modern firearms are by and large fantastic devices. Engineering masterpieces based on centuries of learning and advancement, they tend to be built cost effectively to accurately and reliably send a bullet to a target, a function with many valid purposes from hunting to entertainment to sport to home/auto/self defense, to assuring that a government does not have a monopoly on violence and power. Unfortunately, sometimes some populations allow themselves to be mastered by a political class that does not want the people to be able to defend themselves, and modern firearms are banned.
When guns are outlawed, it is an established fact that outlaws still get them. But the law abiding are in a bind if they want to continue to practice this most basic of human rights. They can move somewhere where civil liberties are still protected (not always possible), or they can become outlaws, or they can simply give up their rights and their self respect. or they can come up with some sort of still-legal workaround. The video below shows one sort of loophole, based on some really quite clever engineering. The heartbreak, of course, is that the cleverly engineered system is still much more expensive than a real firearm and far, far less effective in every sense than a real firearm. Better by far to simply not give up your civil and human rights in the first place.