How does a riot gun differ from an automatic shotgun?
A riot gun is a shotgun with a short barrel, typically 18″ for most applications though there are even shorter barrels used for door breaching and CQC missions. A riot gun may be loaded with non-lethal rounds, but they are not non-lethal weapons, as some answers here have claimed. The only answer that is correct from all the ones posted before mine is from Crazybob. Riot guns are usually pump actions. “Automatic shotguns” are semi-automatic in operation.