Barrel at least eighteen inches. Have reliable witnesses, in case you want to avoid a repeat of Randy Weaver's adventures at Ruby Ridge.
The legal minimum length of a non-rifled gun barrel in the united states is 7 inches.
As long as you don't violate any federal laws or the hunting regulations for your area.
Laws restricting sawed-offs are federal, though there's nothing illegal about shortening the barrel of a shotgun as long as the final product is at least 18 inches.
no
That would depend on the make and model of the shotgun in question,and the length of the barrel/barrels that came with the shotgun.
18
YES. I GUESS.
18.5 inches
18"
18
Yes
is it legal to own a double barrel shotgun in the state of OREGON