Black Powder Guns are firearms that employ early firearm technology, and hand loaded ammunition.
In the event of the collapse of civilization, ammunition production will drop dramatically, and there will come a point when even common ammo varieties start running out. Therefore, a lot of zombie survivalists may consider revertion to the black powder muskets and pistols used over two hundred years ago. The main advantage of black powder guns is that their ammunition is easy for the common person manufacture compared to regular guns. It is far easier to make lead balls and gunpowder than it is to make an equivalent number of bullets. In addition, these weapons fire higher caliber rounds than their modern counterparts do, meaning despite the lack of a rifling barrel, they can still inflict severe damage. However, black powder guns have several critical disadvantages that make their use in any situation (even as a last resort) a highly questionable affair.
Most Black Powder weapons have a long, ardous reloading process. A very well-trained and disciplined infantryman could average three to four shots per minute, while a sub-par one or a militiaman could manage maybe one to two. The average wielder will be lucky to get off one shot per minute. Second, gunpowder becomes useless when it gets wet. And very unstable when it drys from being wet if you fire a re dried powder gun it may cause an explosion of the gun which will probably kill or seriously injure you and no one wants that. Modern cartridges have their powder sealed within the shell. Without such a seal, the weapon may become unusable on rainy days.
Making things worse is the fact that smooth-bore muskets are only accurate out to about 50–75 meters - akin to the effective range of an average handgun, and easily outclassed by every rifle ever made. Yet another downfall for these is they are extremely loud. Most black powder weapons accumulate powder residue with every shot, and must be cleaned every few shots.
While any black powder firearm is quite uncommon, due to the popularity of black powder hunting, these weapons have been gradually making a resurgence over the past few years. Black powder revolvers are capable of holding up to nine shots, with some variants having a shotgun as an attachment; these are still rather slow to reload unless you have a spare cylinder.