If you are smart and work hard you may make something close to a tsunami gun, but if you're reading this in the future then yes. You could make a tsunami gun.
No. The state of Ohio did not invent the paintball gun.
Benjamin Breckinridge Warfield did not invent the BB gun.
No.
gun
anarchy tsunami/the chopper
machine gun
Laser gun.
No.
Gun Powder
An insect-destoyer gun
They have, there was a light-gun developed for the original xbox.
Quite possible.