Guns are becoming easier and easier to manufacture. Ammo is simple to make. Even if you're reduced to absolutely minimal equipment, black powder and muzzleloaders are both something the average person can make at home. Primers are the only really challenging part of modern ammo to make.
Anti-gun folk can try to legislate until they're blue in the face and, like Britain, have lost the plot so bad that they're working on banning kitchen knives. It doesn't matter. The information is out there and would be close to impossible to suppress at this point. Maybe we can hope for that info to be used to mete out justice in unjust societies.