a 12 gauge shotgun can shoot about 30 yards accuracy
Yes, if it is a 10 gauge shotgun.
Depends on the ammunition. Rifled 12 gauge slugs are accurate to about 150 yards
It starts to drop the instant it leaves the barrel
No, you can not shoot anything but 12 gauge shotgun shells through a 12 gauge shotgun. Never use any ammunition other than what the firearm was designed for.
yes
Lacking a slug barrel, improved cylinder works best for slugs.
no
some shoot far and some dont so they all dont shoot the same length
I tried it and it was about 30 ftWhen i tried it i got 10 feet :-( (BwzR)
A 12 gauge shotgun cannot fire 20 gauge shells.
You could eaither shoot dove with a 20 gauge shotgun or a 12 gauge shotgun. You should also use a bird shot shells