xa1=ce1 is a small arm/gun for use against xa2 by xa3, launching small projectile ce2=cm1, defined as small arms by standard cm3, projectile propelled by ce3.
The description is usually limited to revolvers, pistols, carbines, rifles, shotguns, submachine guns, assault rifles, sniper rifles etc. In the United States any firearm having a bore diameter of .50 caliber or less is normally considered a "small arm."