 The drawback is that one loses the primary benefits of a handgun, i.e.portability and concealability, resulting in a weapon almost the size of, but less accurate than, a long-gun, but not much more powerful than a pistol.Also widely produced are semi-automatic and typically longer-barreled derivatives of select-fire submachine guns, such as the FN PS90, HK USC, KRISS Vector, Thompson carbine, CZ Scorpion S1 Carbine and the Uzi carbine.