i dont know about the curved gun, its not just about aiming, i would imagine hydrodynamincs could also be affected..maybe on the way down as you try to keep the gun to your side, the water resistance will build under the curved part and move it up creating drag... I dont know ?? maybe a cross section like a Rhombus, so that it would be hydrodynamic in up-down motion as well as side to side...my drawing skills are not too good, if anyonbody understands what i mean please draw it...
also the barrel would start thicker near the trigger and get thinner as you approch the muzzle to give you a light agile 90 speagun
