If you mean MACHINE guns, the answer is yes.
yes some of them come with grooved barrels,these are used for firing shotgun slugs for deer hunting and other sized medium game.other shotguns can have a barrel that was bought extra and can be swapped back and forth for either small game and deer hunting.
Yes, the barrels are rifled.
you get them on the floor from wooden barrels or steel barrels. then you can switch by using the scroll or the keypad
no
Size, weight
No. The barrels are not rifled
Long barreled gun, with grooves on the inside of barrel- is a rifle. Shorter version is a carbine. Handguns, such as pistols and revolvers also have grooved barrels.
Some did, but not all.
TC is one
Because a spinning bullet travels in a straighter line, for further, than a bullet which is not spinning. So, in a word, "accuracy" is why a gun puts a spin on a bullet. Not all of the guns put spin on the bullet though. Those that do have rifled barrels(grooved on inside). There are also smooth bore guns that do not cause the projectile to spin.
Within reasonable limits, a longer barrel lets the bullet get pushed by the gunpowder for a longer time, and it moves faster.
It could be a cooper- someone that makes wooden barrels. In firearms, a person or company that makes barrels for guns.