@BipolarExpat pretty much is on point here. Handguns and pistols are easier to conceal and move around. Also, they are oftenly used in crimes as gangs and other criminals like to use them to commit their evil deeds/crimes with it. Long guns, while they are deadlier (rifle with a powerful caliber, shotgun with buckshot/slugs, etc.) are harder to conceal and aren't used as often in crimes as that of handguns.