The idea to cut down the barrel only emerged when it became clear that reloading a full-length musket on horseback was a horrible job, even if the enemy weren’t trying to kill you at the same time. Historically, the carbine was only a smaller calibre version of an infantry musket. They are also remarkably difficult opponents for heavy cavalry it is hard to come to grips with an enemy who can simply outpace you! Having the speed of light cavalry, these men are a useful force for any Grand Master: they can be moved quickly to a key part of the line to give fire, and then redeployed with equal speed. Their carbines fire a smaller ball than the muskets of infantrymen, but it is still large enough to maim and kill a target. They are a highly mobile unit, with enough long-range firepower to hurt many enemies the pistols used by some cavalrymen are only really suitable for close-in fighting during a melee. These light cavalry are armed with carbines it is their role to harass enemies with fire.
Carabineers are missile cavalry in Empire: Total War.